CN107966459A - A kind of trickle scuffing on-line measuring device of wide cut surface glass - Google Patents

Abstract

The invention discloses an on-line detection device for fine scratches on wide-format glass, which comprises a detection platform for placing a glass sample to be detected and capable of driving the glass sample to be detected to move thereon; one side of the detection platform is provided with a There is a control execution system; a visual inspection system and a glass pretreatment system straddle both sides of the inspection platform. The present invention can complete the functions of real-time detection, tracking, alarm and information statistics of glass products on the on-site production line, and realize the high-accuracy on-line detection of fine scratches on the wide-width glass surface.

Description

An online detection device for fine scratches on wide-format glass

technical field

The invention relates to the field of machine vision detection, in particular to an online detection device for fine scratches on wide-format glass.

Background technique

Glass products are widely used in aerospace, automobile manufacturing, smart phones, automation instruments, construction engineering, nuclear engineering and other key engineering fields. According to their applications, they are mainly divided into ordinary flat glass, tempered glass, laminated glass and other special glasses. Ordinary flat glass is the original glass. Laminated glass is made by bonding two or more original glass sheets together with synthetic resin. Toughened glass and other special glass are also processed from the original glass. It can be seen that various types of glass original sheets are the basis of glass products. In order to improve the production efficiency and product quality of glass and avoid a large number of waste and defective products, it is necessary to systematically inspect the original glass sheets before deep processing. Quality Inspection.

All aspects of glass product production are completed sequentially on a high-speed production line, so as to meet the production needs of large quantities. The quality inspection of the original glass sheet is to detect the defects (such as defects, bubbles, stones, broken glass, stains, scratches, inclusions, etc.) of the original glass sheet in the previous production process on-line before it is further processed. Determine the quality status and grade of the original glass sheet according to the type and quantity of defects.

After investigation, due to the lack of intelligent detection technology and equipment, the current detection methods for glass products of major domestic glass manufacturers are still in the manual detection stage. However, the continuous improvement of production capacity (high speed, large format) and quality level (high-precision defect identification) has made manual inspection unable to meet the demand. It is mainly reflected in the following aspects: (1) The speed is slow, and it is easy to cause missed detection and false detection; (2) It takes up a lot of resources and cannot guarantee a unified quality standard. At present, the inspection of glass quality has been gradually replaced by the online inspection system based on machine vision.

Machine vision online inspection technology is a branch of the rapid development of artificial intelligence, which uses industrial camera imaging instead of human eyes for measurement and judgment. Its equipment and structure are shown in Figure 1, and three main parts are built on the control bus: motion control and data processing system, industrial camera imaging system and workpiece fixing and motion control device. The production data collected and processed by the industrial computer can be fed back in time to realize real-time online detection of defects.

The existing micro-scratch detection technology on glass surface is mainly machine vision online detection technology. The online detection system for glass surface defects based on machine vision consists of image acquisition part, image processing, input and output part, intelligent control and mechanical execution, as shown in Figure 2. The specific working process is as follows: place the glass to be inspected in front of a controllable background that is illuminated as uniformly as possible (using the red LED light on the back), the intelligent control system sends a control signal to the image acquisition module (CCD camera), and the images captured by the CCD camera The glass surface defect image is collected into the computer memory through the image acquisition card, and the glass surface defect image processing and measurement software is used to realize the detection of the glass surface defect, and finally the detection result is output through the output device.

Glass quality defect detection is based on advanced CCD imaging technology and intelligent light source. The system lighting adopts backlight lighting, and its principle is shown in Figure 3, that is, a light source is placed on the back of the glass, and the light passes through the glass to be inspected and enters the camera. After the light is vertically incident on the glass, when there is no impurity in the glass, the outgoing direction will not change, and the light detected by the target surface of the CCD camera is also uniform; when there are impurities in the glass, the outgoing light will change, and the CCD camera The light detected by the target surface will also change accordingly.

The defects contained in the glass are mainly divided into two types: one is the light absorption type (such as sand grains, tin inclusions), when the light transmits through the glass, the light at the defect position will become weaker, and the light detected on the target surface of the CCD camera The light is weaker than the surrounding light; the second is the light transmission type (such as cracks, bubbles, etc.), the light is refracted at the defect position, and the light intensity is greater than the surrounding light, so the light detected on the target surface of the CCD camera is also Enhanced accordingly.

(1) The existing on-line detection system for glass surface defects based on machine vision generally adopts a line-scanning imaging system. The front light source and the back light source are tilted forward or backward to provide illumination in bright field conditions, and the lines parallel to the scanning lines The light source scans the glass (as shown in Figure 3). This detection method is easy to detect defects parallel to the scanning line (such as sand grains, tin inclusions, air bubbles), but cannot detect the following fine scratches: a, scratches perpendicular to the scanning line; b, wide glass Scratches on irregular scratches. Therefore, after being tested by existing equipment, some defective glass products still flow out, which adversely affects product quality.

(2) The existing technology has the disadvantages of high defect missed detection rate and false detection rate in the online detection process of wide-width glass (greater than 1m), and some methods that can solve this shortcoming have high costs and are not suitable for small and micro enterprises Current status of use.

Contents of the invention

The technical problem to be solved by the present invention is to provide an on-line detection device for fine scratches on wide-format glass to complete the functions of real-time detection, tracking, alarm and information statistics of glass products on the on-site production line, and realize wide High-accuracy online detection of fine scratches on the glass surface.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: an on-line detection device for fine scratches on wide-format glass, including a device for placing the glass sample to be detected and driving the glass sample to be detected to move on it. A detection platform; a control execution system is provided on one side of the detection platform; neither the visual detection system nor the glass pretreatment system has a gantry structure, and spans both sides of the detection platform; the control execution system and the vision The detection system and the glass pretreatment system are electrically connected; the control execution system controls the glass pretreatment system to perform drying, dust and static removal treatment on the glass sample to be tested, and then the detection platform transports the glass sample to be tested to the visual inspection system. Below the detection system, the visual detection system detects minor scratches on the surface of the treated glass sample to be detected.

The glass pretreatment system includes a left frame and a right frame; the left frame and the right frame are connected by a connecting tool; the connecting tool is provided with at least one transparent sensor; the connecting tool is provided with a At least one set of plasma air knives; an air source for driving the plasma air knives is arranged on the left frame and/or the right frame.

The air outlet of the plasma air knife forms an angle of 45° to 60° with the conveying direction of the glass sample to be tested.

The top of the left frame and the top of the right frame are connected through the first protective cover.

The visual execution system includes a first frame and a second frame; the first frame and the second frame are connected through a dark field lighting device; the first frame above the dark field lighting device, the second frame The two racks are connected through an automatic sliding table; a level and a plurality of cameras are arranged on the automatic sliding table.

A second protective cover is arranged above the automatic slide table.

The dark field lighting device includes a left bracket and a right bracket; a light source capable of rotating in the axial direction is installed between the left bracket and the right bracket; a light source reflection working plate is arranged outside the light source, and the light source reflection work The two ends of the plate are respectively fixedly connected with the left bracket and the right bracket.

The automatic slide table includes a slide bar; the slide bar is provided with a plurality of slide blocks that can slide on the slide bar; each slide block is provided with a camera; each of the two ends of the slide bar passes through A connecting rod is respectively connected with the first frame and the second frame, and the connecting rod can move along the width direction of the first frame and the second frame; the slide bar can move along the width of the first frame and the second frame; The linkage moves.

The control execution system includes an industrial control host; the industrial control host is connected to a controller, an alarm system, and a plurality of image acquisition cards; each of the image acquisition cards is connected to a camera; the controller is connected to the dark The field lighting device, the transparent sensor, and the electric connection of the automatic slide table.

All the image acquisition cards are electrically connected with the encoder, and the encoder is electrically connected with the controller.

Compared with the prior art, the present invention has the beneficial effects that: the present invention can complete the functions of real-time detection, tracking, alarm, and information statistics of glass products on the production line on site, and realize the high accuracy of fine scratches on the wide glass surface. Online detection of accuracy.

Description of drawings

Fig. 1 is a system framework block diagram of the embodiment of the present invention;

Fig. 2 is a schematic structural diagram of an embodiment of the present invention;

Fig. 3 is the schematic diagram of the glass pretreatment system of the embodiment of the present invention;

Fig. 4 is a structural diagram of the visual execution system of the present invention;

Fig. 5 is a structural diagram of the dark field lighting device assembly of the present invention;

Fig. 6 is the schematic diagram of automatic control of the system of the present invention;

Fig. 7 is a working flow diagram of the present invention.

Detailed ways

As shown in Figure 1, the present invention is mainly composed of an on-site simulation working condition system, a glass sample to be tested, a warning alarm system, a control execution system, a visual execution system, a protective cover and a glass pretreatment system. The on-site simulation working condition system (that is, the testing platform) is mainly used to simulate the actual production line of glass products. It has functions such as self-starting and pausing, running speed adjustment, and direction adjustment. It is used as a basic stage to simulate various working conditions of the samples to be tested; The glass sample to be tested is the original glass sheet, which can be the glass product in the testing process on the actual production line; the warning alarm system realizes the alarm and prompt function for the detection of defective glass samples; the control execution system integrates all action controls of the device, including: 1. On-site Start and stop, pause, speed regulation and steering of the simulated working condition system, 2. XYZ three-direction movement in the visual execution system, 3. Start and stop, pause and speed regulation of the air knife in the glass pretreatment system, 4. Warning and alarm system 5. The angle adjustment and brightness adjustment of the light source in the dark-field lighting device; the visual execution system is the core of the device, and the visual system is used to realize high-precision detection of various defects in the glass, and the image data is output; the protective cover has Protection of precision parts in the device, light blocking and dustproof functions.

As shown in Figure 2, the glass pretreatment system is installed after the on-site glass cleaning machine in the pilot line, and the glass products to be tested are dried, dust- and static-removed. The system is mainly composed of left and right racks, adjustable connecting devices, ion air knife and connecting pipelines.

Two sets of ion air knives are placed at appropriate positions above and below the pilot test line, and the air outlet is inclined at an angle of 45° to 60° to the conveying direction of glass products. The ion bar produces a large number of positive and negative ions under high pressure. The air curtain blown by the air knife acts as a carrier to bring a large number of ions to the surface of the glass to be tested, and quickly neutralizes the static electricity on the surface. The air curtain can also effectively remove water stains on the surface , dust and other particles. In the overall structure, the glass pretreatment system and the visual execution system are combined in a flexible and airtight manner to prevent secondary pollution. The addition of this system can effectively remove the residual water stains and fluff on the glass products to be tested, and at the same time remove the static electricity on the glass products. It plays a key role in ensuring the pass rate of product testing and reducing the rate of misjudgment.

The line-scan camera selected according to the calculation is installed on a set of XYZ three-dimensional adjustable automatic sliding table device. According to the actual situation of the production line and glass products, the line-scan camera can be adjusted in the following three aspects:

X direction: adjust the working width of the line scan camera (manual adjustment)

Y direction: adjust the relative position of the line scan camera and the intelligent light source (manual adjustment)

Z direction: adjust the height of the camera to achieve precise focus (automatic adjustment)

The automatic sliding table is supported by racks on the left and right, forming a gantry structure. Both the left and right ends of the frame are welded by steel structure, and the bottom is equipped with universal wheels with damping adjustment bolts, which is convenient for the overall movement and fixing of the detection system, and at the same time ensures the stability of the camera lens.

The dark-field lighting device assembly is installed across the racks at both ends, and the height can be adjusted left and right according to the actual situation of the production line to ensure that the light source can form a suitable optical path system with the line array camera. As shown in Figure 5, the dark-field lighting device includes a left bracket 531, a right bracket 532, a light source 534 and a light source reflection working plate 537 are arranged between the left bracket 531 and the right bracket 532, and the two ends of the light source 534 are respectively connected to the shaft coupling by a connecting piece 533. 535 connection, two shaft couplings 535 are respectively connected with a speed reducer 536 output shaft, and two speed reducers are respectively fixed on the left support 531, the right support 532. The controller drives the reducer to rotate, and the reducer drives the light source to rotate axially.

The XYZ three-dimensional adjustable automatic sliding table device is integrated and installed on the frame, and the height of the installation position controls its accuracy. The level instrument detects it in real time during installation, so that it can meet the requirements of the camera. If the gantry structure cannot be installed in some production line installation locations, the mechanical structure can also be modularized and disassembled for reassembly.

The protective cover is formed by bending a thin plate, and the internal welding keel is strengthened. The protective cover is equipped with a steel handle, which is convenient for the switch and closure of the protective cover. The fixed clamping of the protective cover can be realized by quickly pressing the buckle when closing. Open the pneumatic adjustment door at the center of the protective cover to facilitate the inspection and maintenance of the vision system. The function of the protective cover: to protect the actuator and block the interfering light source.

Description of the implementation mode (as shown in Figure 7):

(1) Roughly adjust the three directions of XYZ according to the style of glass products to determine the initial position of the line scan camera. Through image preview, real-time feedback to adjust the drive motor, control the movement of the sliding table, so as to achieve precise focus of the camera;

(2) Adjust the position and lighting mode of the intelligent backlight light source according to the position of the camera, and the dark field lighting device starts the backlight linear lighting in advance;

(3) When the glass to be tested is transported to the glass pretreatment system, the transparent sensor detects its position and transmits the signal to the controller. The controller performs delay processing, and the ion air knife is turned on and running;

(4) The glass products are transported to the position of the encoder (the encoder is installed concentrically with the running shaft of the on-site simulation working condition system), the actual running speed of the production line is measured, and the signal is transmitted to the controller;

(5) The line array camera captures the image of the first detected product, and transmits it to the image acquisition card through the data line. The encoder sends a real-time speed signal to the image acquisition card, and the image data is processed by the acquisition card and then sent to the industrial computer;

(6) In the pre-verified setting mode, the dark field lighting device starts the reducer, the linear light source is adjusted to the first calculation angle (adjusted by the rotation of the reducer), the glass to be tested is returned and transmitted, and the light is reflected by the light source and the working plate To the glass surface to be inspected, dark-field illumination is realized, and the line-scan camera captures the image of the second inspected product.

(7) In the pre-verified setting mode, the dark-field lighting device starts the reducer, the linear light source is adjusted to the second calculation angle, the glass to be tested is transmitted forward in the original state, and the light is reflected by the light source reflection working plate 537 to the to-be-tested The glass surface realizes dark-field illumination, and the line-scan camera captures the image of the third product detected.

(8) Process the collected images to obtain the required image information and processing results. The final information is displayed in real time through the display, and external events are associated with the on-site IO to output control signals. For example, when unqualified glass products are detected, the warning alarm system is triggered immediately, and at the same time, a switch command is sent to the pilot line controller;

(9) When changing the specifications and models of glass products, the operator selects the corresponding glass size on the human-computer interface, and the camera can realize automatic focusing, which can adapt to the online detection of various products and multiple production lines.

Claims (10)

1. An online detection device for fine scratches on wide-format glass, characterized in that it includes a detection platform (1) for placing the glass sample to be detected (2) and driving the glass sample to be detected to move on it ; One side of the detection platform (1) is equipped with a control execution system (3); the visual detection system (5) and the glass pretreatment system (7) are both gantry structures, and the visual detection system (5) and the glass The pretreatment system (7) is across both sides of the detection platform (1); the control execution system (3) is electrically connected with the visual detection system (5) and the glass pretreatment system (7); the The control execution system (5) controls the glass pretreatment system (7) to perform drying, dust and static removal treatment on the glass sample (2) to be tested, and then the detection platform (1) transports the glass sample (2) to be tested to Below the visual inspection system (5), the visual inspection system (5) detects minor scratches on the surface of the treated glass sample (2) to be inspected. 2. The on-line detection device for fine scratches on wide-format glass according to claim 1, characterized in that, the glass pretreatment system (7) includes a left frame (71) and a right frame (72); The left frame (71) and the right frame (72) are connected by a connecting tool (73); at least one transparent sensor (74) is arranged on the connecting tool (73); There is at least one set of plasma air knives (75); an air knife air source (76) for driving the plasma air knives (75) is arranged on the left frame (71) and/or the right frame (72). 3. The on-line detection device for fine scratches on wide-format glass according to claim 2, characterized in that the air outlet of the plasma air knife (75) is at an angle of 45° to the conveying direction of the glass sample (2) to be detected. 60º angle. 4. The on-line detection device for fine scratches on wide-format glass according to claim 2, characterized in that the top of the left frame (71) and the top of the right frame (72) are connected by a first protective cover (77) . 5. The on-line detection device for fine scratches on wide-format glass according to claim 2, characterized in that, the visual execution system (5) includes a first frame (51) and a second frame (52); The first frame (51) and the second frame (52) are connected through a dark field lighting device (53); the first frame (51) and the second frame above the dark field lighting device (53) The frames (52) are connected by an automatic sliding table (54); the automatic sliding table (54) is provided with a level (55) and a plurality of cameras (56). 6 . The on-line detection device for fine scratches on wide-format glass according to claim 5 , characterized in that, a second protective cover ( 57 ) is arranged above the automatic slide table ( 54 ). 7. The on-line detection device for fine scratches on wide-format glass according to claim 5, characterized in that the dark-field lighting device (53) includes a left bracket (531) and a right bracket (532); the left bracket A light source (534) capable of rotating axially is installed between (531) and the right bracket (532); the light source (534) is provided with a light source reflection working plate (537), and the light source reflection work plate (537 ) are fixedly connected to the left bracket (531) and the right bracket (532) respectively. 8. The on-line detection device for fine scratches on wide-format glass according to claim 5, characterized in that, the automatic slide table (54) includes a slide bar; A slider that slides on the rod; each of the sliders is provided with a camera (56); each of the two ends of the slider is respectively connected to the first frame (51) and the second frame through a connecting rod (52) are connected, and the connecting rod can move along the width direction of the first frame (51) and the second frame (52); the sliding rod can move along the connecting rod. 9. The on-line detection device for fine scratches on wide-format glass according to claim 5, characterized in that, the control execution system (3) includes an industrial control host; the industrial control host and a controller, an alarm system, Multiple image acquisition cards are connected; each image acquisition card is connected to a camera (56); the controller is electrically connected to the dark field lighting device (53), transparent sensor (74), and automatic sliding table (54). connect. 10 . The on-line detection device for fine scratches on wide-format glass according to claim 9 , wherein all image acquisition cards are electrically connected to encoders, and the encoders are electrically connected to the controller. 11 .