Glass flatness detection device and method

Abstract

The invention belongs to the technical field of flatness detection equipment, and specifically relates to a glass flatness detection device and method, wherein the detection device comprises a working platform and a detection box; the detection box comprises a box body, a laser is vertically installed on the upper part of the box body, and a beam shaping system and a CCD camera are installed in the box body; a through hole is opened at the bottom of the detection box, and a standard glass and an inclination adjustment device are installed at the through hole, and the inclination adjustment device can adjust the inclination of the standard glass relative to the horizontal plane; compared with the prior art, the advantages and positive effects of the invention are: when the glass flatness detection device of the invention is used to check the level of the glass, the working platform is made level by adjusting the electric telescopic rod three, so that the influence of the horizontal deviation of the working platform on the detection accuracy can be avoided; when the spacing of the interference fringes needs to be adjusted, the piston rod of the electric telescopic rod one is controlled to extend or shorten; the interference fringes spacing changes, so as to adapt to different degrees of convex or concave defects.

Description

Technical Field

[0001] The invention belongs to the technical field of flatness detection equipment, and in particular relates to a glass flatness detection device and method. Background Art

[0002] The methods used to determine or measure the flatness of glass in the prior art mainly adopt methods such as wedge interferometry, machine vision or contact measurement. Among them, the detection efficiency of the machine vision method is low, and the contact measurement has problems such as contact with the glass causing damage to the glass. The wedge interferometry is essentially equal thickness interference. The glass sample to be detected is used as the lower bottom surface of the wedge to obtain an interference pattern. The flatness of the sample can be determined by observing the concavity of the interference pattern, that is, the flatness of the component is indirectly detected. By analyzing the optical path difference, when the sample plane is flat, the thickness changes uniformly, and the interference fringes obtained under the microscope are smooth straight lines; when there is a depression on the sample plane, the interference fringes are biased towards the wedge edge; if there is a convexity on the sample plane, the fringes are biased away from the wedge edge, so that the interference pattern is obtained by using the wedge interferometry principle, and the surface flatness of the glass can be detected, but the results obtained by the wedge interferometry method have low accuracy and low precision.

[0003] The reasons why the wedge interferometry method is not accurate enough in detecting the flatness of glass include the horizontal deviation of the detection table, which leads to inaccurate detection results during detection; the control requirements for the wedge angle are high, and the wedge angle needs to be adjusted to a suitable level to more accurately calculate the value of the protrusion or depression.

[0004] In addition, when the wedge-tip interferometry method is used in the prior art to detect the flatness of glass, it is necessary to randomly select samples from products of the same model and specification and the same batch, and the specifications of the samples are generally 600mm×100mm; the disadvantages of this approach are: some glass products with flatness defects may not be sampled, resulting in misjudgment of quality; in addition, the sampling work is labor-intensive and causes loss of yield rate. Summary of the invention

[0005] The present invention aims at the technical problem that the wedge-tip interferometry method used in the prior art is not accurate enough in detecting the flatness of glass and causes a loss in yield rate, and provides a glass flatness detection device and method.

[0006] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is as follows: a glass flatness detection device, comprising a working platform and a detection box; the detection box comprises a box body, a laser is vertically installed on the upper part of the box body, a beam shaping system and a CCD camera are installed in the box body, the output light of the beam shaping system enters the CCD camera, and the CCD camera is connected to an external computer for communication;

[0007] A through hole is provided at the bottom of the detection box, and a standard glass and an inclination adjustment device are installed at the through hole. The inclination adjustment device can adjust the inclination of the standard glass relative to the horizontal plane; the glass to be detected is placed on the working platform; and the detection box is located above the glass to be detected.

[0008] Preferably, the tilt adjustment device comprises an electric telescopic rod 1, which is horizontally mounted on the lower end of the side wall of the detection box, a push block is fixedly connected to the end of the piston rod of the electric telescopic rod 1, and a hard gasket is fixedly connected below the push block; in horizontal projection, the push block is at the end of the hard gasket; the end of the upper surface of the hard gasket away from the push block is slidably connected to one side of the lower surface of the standard glass; the lower surface of the hard gasket fits the bottom surface of the detection box; the electric telescopic rod 1 is connected to an external computer for communication;

[0009] The end of the standard glass away from the hard gasket is hinged to the detection box through a hinge shaft; the positioning accuracy of the electric telescopic rod 1 reaches 0.01mm or higher; the thickness of the hard gasket is 0.01-0.1mm.

[0010] Preferably, the beam shaping system comprises an upper aperture, a right aperture, a semi-transparent and semi-reflective mirror and a convex lens.

[0011] Preferably, the plurality of detection boxes are evenly distributed above the glass to be detected and distributed along the width direction of the glass to be detected.

[0012] Preferably, two electric telescopic rods are horizontally installed on both sides of the width of the working platform, and the piston rod ends of the two electric telescopic rods are fixedly connected to push plates, which can push the glass to be inspected on the working platform to move along the width direction.

[0013] Preferably, a spirit level is also installed on the upper surface of the working platform; a height adjustment device is installed on the lower part of the working platform, and the height adjustment device includes four electric telescopic rods three, and the four electric telescopic rods three are respectively located under the corners of the working platform and support the working platform.

[0014] Preferably, the glass flatness detection device further comprises a ball screw and a slider, wherein the electric telescopic rod is vertically mounted on the upper surface of the slider; the slider cooperates with the horizontal ball screw; and the ball screw is parallel to the length direction of the working platform.

[0015] Preferably, a polished rod is installed on both sides of the ball screw respectively, and the slider is slidably connected to the two polished rods.

[0016] Preferably, glass conveying rollers and glass suction cups are respectively arranged at both ends of the ball screw in the length direction, and the slider can drive the working platform to dock with the glass conveying rollers.

[0017] A glass flatness detection method, characterized in that the whole glass is checked for flatness using the glass flatness detection device, comprising the following steps:

[0018] Step 1: The slider drives the working platform to move and dock with the glass conveyor roller, and the glass to be tested is transferred from the glass conveyor roller to the upper surface of the working platform;

[0019] Step 2: According to the thickness of the glass to be tested, adjust the electric telescopic rod 3 so that the working platform is level and the distance from the upper surface of the glass to be tested to the bottom of the test box meets the test requirements;

[0020] Step 3: The slider drives the working platform and the glass to be tested to move toward the testing box, and the flatness test is performed on different positions of the length direction of the glass to be tested; at the same time, multiple testing boxes perform flatness tests on different positions of the width direction of the glass to be tested; when the testing position in the width direction needs to be changed, the electric telescopic rod 2 is used to push the glass to be tested on the working platform to move along the width direction; when the spacing of the interference fringes needs to be adjusted, the piston rod of the electric telescopic rod 1 is controlled to extend or shorten;

[0021] Step 4: An external computer connected to the CCD camera in each test box stores and displays the interference fringes. At the same time, the external computer can compare the calculated convex or concave value of the glass surface to be tested with the set value, thereby obtaining a test conclusion as to whether the convex or concave value of the glass surface to be tested is within the allowable range.

[0022] Step 5: The slider drives the working platform and the glass to be tested to move away from the end of the glass conveyor roller; the glass suction cup removes the glass that has completed the flatness test from the upper surface of the working platform, and repeats steps 1 to 5.

[0023] Compared with the prior art, the advantages and positive effects of the present invention are:

[0024] (1) When the glass flatness detection device of the present invention is used to check the flatness of glass, the working platform can be made level by adjusting the electric telescopic rod 3 to avoid the influence of the horizontal deviation of the working platform on the detection accuracy;

[0025] (2) When the spacing of the interference fringes needs to be adjusted, the piston rod of the electric telescopic rod 1 is controlled to extend or shorten, the wedge angle θ changes, and the interference fringes spacing L changes, which can adapt to different degrees of convex or concave defects and facilitate accurate calculation of the convex or concave values; when the wedge angle θ decreases, the interference fringes spacing L increases; and when the wedge angle θ increases, the interference fringes spacing L decreases; by adjusting the interference fringes spacing L, it can be ensured that the interference fringes caused by the convexity or concave are clearly presented between the two interference fringes;

[0026] (3) When the glass flatness detection device of the present invention is used to check the flatness of glass, it is no longer necessary to cut samples from the glass product, which reduces the labor intensity of the operator and improves the glass yield rate;

[0027] (4) The glass flatness detection device of the present invention can be used to detect the flatness of any position of the entire glass, and the detection efficiency is high;

[0028] (5) The glass flatness detection device of the present invention can be applied to online detection of glass flatness. The detection result is displayed through an external computer. If the flatness quality of the glass product is abnormal, the operator can be reminded in time to conduct targeted inspection of the equipment to reduce losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following is a brief introduction to the drawings required for describing the embodiment:

[0030] Figure 1 It is a three-dimensional diagram of a glass flatness detection device;

[0031] Figure 2 It is a top view of the glass flatness detection device;

[0032] Figure 3 This is the front view of the glass flatness detection device;

[0033] Figure 4 for Figure 1 A magnified view of the working platform and level gauge at center A;

[0034] Figure 5 It is a schematic diagram of the distribution of multiple detection boxes in the glass flatness detection device;

[0035] Figure 6 It is a schematic diagram of the internal structure of the detection box in the glass flatness detection device;

[0036] Figure 7 It is a schematic diagram of the inclination adjustment device in the glass flatness detection device;

[0037] Figure 8 This is a schematic diagram of the through hole at the bottom of the detection box in the glass flatness detection device;

[0038] Fig. 9 This is the interference fringe pattern obtained during the detection process of the detection box.

[0039] Description of reference numerals:

[0040] 1—Glass conveyor roller;

[0041] 2—base, 21—ball screw, 22—polished rod;

[0042] 3-slider, 4-electric telescopic rod 3, 5-working platform;

[0043] 6—detection box, 61—box, 62—laser, 63—bracket, 64—upper aperture, 65—semi-transparent and semi-reflective mirror, 66—right aperture, 67—CCD camera, 68—convex lens;

[0044] 7—electric telescopic rod 2, 8—level, 9—hard gasket, 10—electric telescopic rod 1, 11—standard glass, 12—hinge shaft, 13—pushing block. DETAILED DESCRIPTION

[0045] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described below with reference to the accompanying drawings and embodiments.

[0046] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0047] Example 1

[0048] Combine the following Figure 1-Figure 9 The glass flatness detection device in Example 1 is further described as follows: Figure 1-Figure 3 As shown, it includes a working platform 5, a detection box 6 and a controller; the detection box 6 includes a box body 61, a laser 62 (wavelength λ) is vertically installed on the upper part of the box body 61, a beam shaping system and a CCD camera 67 are installed in the box body 61, the output light of the beam shaping system enters the CCD camera 67, and the CCD camera 67 is connected to the external computer for communication.

[0049] like Figure 6-Figure 8 As shown, a through hole is opened at the bottom of the detection box 6, and a standard glass 11 and an inclination adjustment device are installed at the through hole. The inclination adjustment device can adjust the inclination of the standard glass 11 relative to the horizontal plane; the glass to be detected is placed on the working platform 5; and the detection box 6 is above the glass to be detected.

[0050] like Figure 7 As shown, the tilt adjustment device includes an electric telescopic rod 10, which is horizontally installed at the lower end of the side wall of the detection box 6. The end of the piston rod of the electric telescopic rod 10 is fixedly connected to a push block 13, and a hard gasket 9 is fixedly connected below the push block 13; the electric telescopic rod 10 is connected to the controller for communication. In horizontal projection, the push block 13 is at the end of the hard gasket 9; the end of the upper surface of the hard gasket 9 away from the push block 13 is slidably connected to one side of the lower surface of the standard glass 11; the lower surface of the hard gasket 9 is in contact with the inner bottom surface of the detection box 6. The electric telescopic rod 10 is connected to the external computer for communication.

[0051] like Figure 6 and Figure 7 As shown, the end of the standard glass 11 away from the hard gasket 9 is hinged to the detection box 6 through the hinge shaft 12; the positioning accuracy of the electric telescopic rod 10 reaches 0.01mm or higher; the thickness of the hard gasket 9 is 0.01-0.1mm.

[0052] like Figure 6 and Figure 7 As shown, both ends of the hinge shaft 12 are fixedly connected to the side walls of the detection box 6; the axis of the hinge shaft 12 is flush with the inner bottom surface of the detection box 6. The standard glass 11 has a steel edging on the side close to the hinge shaft 12; the middle part of the hinge shaft 12 has a small diameter, and a sleeve is sleeved on the outer periphery of the middle part (the inner diameter of the sleeve is equal to the outer diameter of the middle part), and the outer part of the sleeve is fixedly connected to the lower end of the steel edging through a connecting rod. When the hard gasket 9 is pulled out from under the standard glass 11, the lower surface of the standard glass 11 can fit with the inner bottom surface of the detection box 6 and the standard glass 11 is horizontal at this time.

[0053] The inclination angle of the standard glass 11 relative to the horizontal plane is the wedge tip angle θ in the wedge tip interference; in this embodiment, the hard gasket 9 is made of stainless steel foil with a thickness of 0.015 mm, and the positioning accuracy of the electric telescopic rod 10 is 0.01 mm.

[0054] The beam shaping system includes an upper aperture 64, a right aperture 66, a semi-transparent and semi-reflective mirror 65 and a convex lens 68. The optical path is as follows: Figure 6 shown.

[0055] like Figure 2 and Figure 5 As shown, a plurality of detection boxes 6 are evenly distributed above the glass to be detected (a plurality of boxes 61 are installed on a bracket 63), and are distributed along the width direction of the glass to be detected.

[0056] like Figure 2 and Figure 4 As shown, two electric telescopic rods 7 are horizontally installed on both sides of the width of the working platform 5, and the piston rod ends of the electric telescopic rods 7 are fixedly connected with push plates, which can push the glass to be inspected on the working platform 5 to move along the width direction. The electric telescopic rods 7 are in communication connection with the controller.

[0057] like Figure 2 and Figure 4 As shown, a level 8 (universal level) is also installed on the upper surface of the working platform 5; a height adjustment device is installed at the lower part of the working platform 5, and the height adjustment device includes four electric telescopic rods 3 4, which are respectively located under the corners of the working platform 5 and support the working platform 5. The electric telescopic rods 3 4 are connected to the controller for communication.

[0058] like Figure 1-Figure 3As shown, the glass flatness detection device also includes a ball screw 21 and a slider 3, and the electric telescopic rod 3 4 is vertically installed on the upper surface of the slider 3; the slider 3 cooperates with the horizontal ball screw 21; the ball screw 21 is parallel to the length direction of the working platform 5. The ball screw 21 is driven by a servo motor, and the servo motor is connected to the controller for communication.

[0059] like Figure 1-Figure 3 As shown, a polished rod 22 is installed on both sides of the ball screw 21, and the slider 3 is slidably connected to the two polished rods 22. The ball screw 21 and the polished rod 22 are both installed on the base 2.

[0060] like Figure 1-Figure 3 As shown, a glass conveying roller 1 and a glass suction cup are respectively arranged at both ends of the ball screw 21 in the length direction, and the slider 3 can drive the working platform 5 to dock with the glass conveying roller 1.

[0061] A glass flatness detection method, such as Figure 1-Figure 3 As shown, the above-mentioned glass flatness detection device is used to check the flatness of the entire glass, including the following steps:

[0062] Step 1: The slider 3 drives the working platform 5 to move and dock with the glass conveyor roller 1, and the glass to be tested is transferred from the glass conveyor roller 1 to the upper surface of the working platform 5;

[0063] Step 2: According to the thickness of the glass to be tested, adjust the electric telescopic rod 3 4 so that the working platform 5 is level and the distance from the upper surface of the glass to be tested to the bottom surface of the test box 6 meets the test requirements;

[0064] Step 3: The slider 3 drives the working platform 5 and the glass to be tested to move toward the testing box 6, and performs flatness testing on different positions of the glass to be tested in the length direction; at the same time, multiple testing boxes 6 perform flatness testing on different positions of the glass to be tested in the width direction; when it is necessary to change the testing position in the width direction, the electric telescopic rod 2 7 is used to push the glass to be tested on the working platform 5 to move along the width direction; when it is necessary to adjust the spacing of the interference fringes, the piston rod of the electric telescopic rod 10 is controlled to extend or shorten;

[0065] Step 4: The external computer connected to the CCD camera 67 in each detection box 6 stores and displays the interference fringes. At the same time, the external computer can compare the calculated convexity or concave value of the glass surface to be detected with the set value, so as to obtain a detection conclusion whether the convexity or concave value of the glass surface to be detected is within the allowable range;

[0066] Step 5: The slider 3 drives the working platform 5 and the glass to be tested to move away from the end of the glass conveyor roller 1; the glass suction cup removes the glass that has completed the flatness test from the upper surface of the working platform 5, and repeats steps 1 to 5.

[0067] The present invention uses wedge-tip interferometry to measure the convexity or concavity of the glass surface, and calculates the convexity or concavity according to the interference fringe spacing L, as follows: Fig. 9 As shown, the concavity value is calculated based on how much the stripes bend to the left.

[0068] The calculation formula for the interference fringe spacing L is: L=λ / (2nsinθ)≈λ / 2nθ.

[0069] In step 4, the interference fringe interface displayed by the external computer carries the interference fringe spacing L value, which is calculated according to the above formula, wherein the wavelength λ of the laser emitted by the laser 62 is known, and the refractive index n of air is 1; the wedge angle θ is calculated by arctan(h / the distance from the hard gasket 9 to the axis center of the hinge shaft 12), where h is the thickness of the hard gasket 9; initially, the distance from the hard gasket 9 to the axis center of the hinge shaft 12 is known, and when the piston rod of the electric telescopic rod 10 is controlled to be extended or shortened, the wedge angle θ changes, and the interference fringe spacing L changes.

[0070] Example 2

[0071] The difference between this embodiment and embodiment 1 is that the hard gasket 9 in this embodiment is made of copper foil with a thickness of 0.01 mm.

[0072] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes for application in other fields. However, any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A glass flatness detection device, characterized in that: It comprises a working platform (5) and a detection box (6); The detection box (6) comprises a box body (61), a laser (62) is vertically mounted on the upper part of the box body (61), a beam shaping system and a CCD camera (67) are mounted inside the box body (61), output light of the beam shaping system enters the CCD camera (67), and the CCD camera (67) is connected to an external computer for communication; The bottom of the detection box (6) is provided with a through hole, and a standard glass (11) and an inclination adjustment device are installed at the through hole, and the inclination adjustment device can continuously adjust the inclination of the standard glass (11) relative to the horizontal plane; the glass to be detected is placed on the working platform (5); and the detection box (6) is located above the glass to be detected; The tilt adjustment device comprises an electric telescopic rod (10), the electric telescopic rod (10) being horizontally mounted at the lower end of the side wall of the detection box (6), the piston rod end of the electric telescopic rod (10) being fixedly connected to a push block (13), and a hard gasket (9) being fixedly connected below the push block (13); in horizontal projection, the push block (13) is located at the end of the hard gasket (9); the end of the upper surface of the hard gasket (9) away from the push block (13) is slidably connected to one side of the lower surface of the standard glass (11); the lower surface of the hard gasket (9) is in contact with the inner bottom surface of the detection box (6); the electric telescopic rod (10) is connected to an external computer for communication; The end of the standard glass (11) away from the hard gasket (9) is hinged to the detection box (6) through a hinge shaft (12); the positioning accuracy of the electric telescopic rod (10) reaches 0.01 mm or higher; the thickness of the hard gasket (9) is 0.01-0.1 mm; The plurality of detection boxes (6) are evenly distributed above the glass to be detected and distributed along the width direction of the glass to be detected.

2. The glass flatness detection device according to claim 1, characterized in that: The beam shaping system comprises an upper aperture (64), a right aperture (66), a semi-transparent and semi-reflective mirror (65) and a convex lens (68).

3. The glass flatness detection device according to claim 1, characterized in that: Electric telescopic rods (7) are horizontally mounted on both sides of the width of the working platform (5), and the piston rod ends of the electric telescopic rods (7) are fixedly connected to push plates, which can push the glass to be inspected on the working platform (5) to move along the width direction.

4. The glass flatness detection device according to claim 3, characterized in that: A level (8) is also installed on the upper surface of the working platform (5); a height adjustment device is installed at the lower part of the working platform (5), and the height adjustment device includes four electric telescopic rods (4). The four electric telescopic rods (4) are respectively located below the corners of the working platform (5) and support the working platform (5).

5. The glass flatness detection device according to claim 4, characterized in that: The glass flatness detection device also includes a ball screw (21) and a slider (3); the electric telescopic rod (4) is vertically mounted on the upper surface of the slider (3); the slider (3) cooperates with the horizontal ball screw (21); and the ball screw (21) is parallel to the length direction of the working platform (5).

6. The glass flatness detection device according to claim 5, characterized in that: A polished rod (22) is respectively installed on both sides of the ball screw (21), and the slider (3) is slidably connected to the two polished rods (22).

7. The glass flatness detection device according to claim 6, characterized in that: Glass conveying rollers (1) and glass suction cups are respectively arranged at both ends of the ball screw (21) in the length direction, and the slider (3) can drive the working platform (5) to dock with the glass conveying rollers (1).

8. A glass flatness detection method, characterized in that: Using the glass flatness detection device according to claim 7 to check the flatness of the entire glass comprises the following steps: Step 1: The slider (3) drives the working platform (5) to move and dock with the glass conveying roller (1), and the glass to be inspected is transferred from the glass conveying roller (1) to the upper surface of the working platform (5); Step 2: According to the thickness of the glass to be tested, adjust the electric telescopic rod 3 (4) so ​​that the working platform (5) is level and the distance from the upper surface of the glass to be tested to the bottom surface of the test box (6) meets the test requirements; Step 3: The slider (3) drives the working platform (5) and the glass to be tested to move toward the testing box (6), and performs a flatness test on different positions in the length direction of the glass to be tested; at the same time, multiple testing boxes (6) perform a flatness test on different positions in the width direction of the glass to be tested; when it is necessary to change the testing position in the width direction, the electric telescopic rod 2 (7) is used to push the glass to be tested on the working platform (5) to move along the width direction; when it is necessary to adjust the spacing of the interference fringes, the piston rod of the electric telescopic rod 1 (10) is controlled to extend or shorten; Step 4: an external computer connected to the CCD camera (67) in each detection box (6) stores and displays the interference fringes, and the external computer can compare the calculated convexity or concave value of the glass surface to be detected with the set value, thereby obtaining a detection conclusion of whether the convexity or concave value of the glass surface to be detected is within the allowable range; Step 5: The slider (3) drives the working platform (5) and the glass to be tested to move away from the end of the glass conveying roller (1); the glass suction cup removes the glass that has completed the flatness test from the upper surface of the working platform (5), and repeats steps 1 to 5.

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