WO2019062296A1

WO2019062296A1 - Glass flaw detecting device

Info

Publication number: WO2019062296A1
Application number: PCT/CN2018/096471
Authority: WO
Inventors: 郭裕强; 陈志忠; 刘庆柏; 雷国韬; 卢坤; 田世海; 曾勇展; 尹建兵
Original assignee: 深圳精创视觉科技有限公司
Priority date: 2017-09-27
Filing date: 2018-07-20
Publication date: 2019-04-04
Also published as: CN107607549A

Abstract

A glass flaw detecting device, belonging to the field of product flaw detection. The glass flaw detecting device comprises: a main machine support (10), a conveying unit (20), an illuminating unit (30), an imaging unit (40), an image acquisition unit (50), a rotatable adjustment mechanism (60), a data processing unit (70), and a control unit (80). The rotatable adjustment mechanism (60) is provided on the main machine support (10). The illuminating unit (30) and the image acquisition unit (50) are provided on the rotatable adjustment mechanism (60). The rotatable adjustment mechanism (60) adjusts the relative positions of the illuminating unit (30) and the image acquisition unit (50), such that the image acquisition unit (50) switches between light and dark fields according to detection requirements. The glass flaw detecting device integrates at one detection position a plurality of illumination modes, an imaging lens (40) for different angles, and line scan cameras (51, 52), satisfying multiple flaw detection requirements, thereby improving the efficiency of detection. The invention is suitable for an assembly line work environment, featuring a low reported error rate and highly precise detection. The invention is capable of working stably for a long time, saving a large amount of labor and has great potential for widespread application.

Description

Glass defect detecting device

Technical field

The invention belongs to the field of product defect detection, and particularly relates to various defect detecting devices for a mobile phone cover glass.

Background technique

As people's requirements for product quality are getting higher and higher, appearance quality has become an important factor for consumers to choose electronic products. Mobile phone cover glass is a kind of tempered glass, and tempered glass is also called tempered glass. It is a kind of prestressed glass. Usually, chemical or physical methods are used to form compressive stress on the surface of the glass. When the glass is subjected to external force, the surface pressure is first offset, thereby improving the bearing capacity. Therefore, the tempered glass is widely used in mobile phone screens, building doors and windows, glass curtain walls, electronic instruments and the like. In the manufacturing process of tempered glass, it is necessary to place a metal fixed support on the upper surface of the glass to ensure the parallelism of the glass. However, due to the different material properties of the glass material and the metal fixed support, the expansion coefficients of the two are greatly different, resulting in tempering treatment. After the completion, the flatness and thickness of the glass itself are difficult to ensure uniformity, and it is easy to cause various defects such as chipping, unevenness, white spots, crushing, scratches, tooth defects, IR black and white spots, etc. after tempering. The existence of various defects on the glass surface not only affects the appearance of products such as mobile phone cover glass, but also directly affects the performance of the mobile phone cover when the defects are serious, so how to quickly, efficiently and intelligently temper the cover glass of the mobile phone The detection of glass surface defects is not only related to the development of the enterprise, but also has a very important significance for all relevant industries.

For the detection of tempered glass defects, the traditional methods are mostly manual identification by artificial eyes. This detection method has low detection efficiency, high labor intensity for detection, and long-term work is easy to cause visual fatigue, resulting in low detection accuracy, although it has appeared on the market. A variety of related testing equipment, but the existing testing equipment is complex in structure, high in manufacturing cost, and has an extremely high error rate for detecting internal defects, hole edge defects and side defects. More importantly, at present, the detection function of the detection equipment is single, and it is impossible to carry out all-round inspection of all defects of the inspection product. In the face of multiple defect detection requirements, only a variety of detection equipment can be purchased, which requires occupying a large area of measurement space. The inspection site has high requirements and requires a lot of manpower to be wasted, and the detection efficiency is very low.

Summary of the invention

The object of the present invention is to solve the above-mentioned deficiencies of the prior art, and provide various defects for detecting the cover glass of the mobile phone in an all-round manner, which can be applied to a fast-paced working state of the pipeline, high detection efficiency, large manpower saving, and high detection precision. Glass defect detection device.

The technical solution adopted by the present invention to solve the above deficiencies of the prior art is:

A glass defect detecting device, comprising:

a frame body for carrying a component disposed thereon;

a conveying unit disposed at an upper end of the frame body for conveying the workpiece to be inspected;

a lighting unit disposed on the frame body for providing illumination for defect detection;

An imaging unit, the light emitted by the illumination unit passes through the image to be inspected and enters the imaging unit for imaging;

An image acquisition unit that connects the imaging unit and acquires an image obtained by the imaging unit;

a data processing unit, connected to the image acquisition unit, and performing calculation processing on the image collected by the image acquisition unit;

a rotation adjustment mechanism disposed on the frame body, the illumination unit and the image acquisition unit being disposed on the rotation adjustment mechanism, the rotation adjustment mechanism being between the illumination unit and the image acquisition unit The mutual positional relationship is adjusted to enable the image acquisition unit to perform bright and dark field transformation according to the detection needs;

The control unit is electrically connected to the transmitting unit, the image collecting unit, and the data processing unit, respectively.

Preferably, in the rotation adjusting mechanism of the present invention, the frame body is provided with a fixing frame and a rotating arm, the rotating arm is provided at least one, and the rotating arm can perform 360° continuous rotation. By setting the 360° rotation of the rotating arm, the mutual positional relationship between the illumination unit and the image acquisition unit can be conveniently and quickly adjusted, so that the image acquisition unit can perform bright and dark field changes according to the actual needs of the detection. Meet a variety of defect detection requirements and improve detection efficiency.

Preferably, the rotating arm of the present invention comprises a first rotating arm and a second rotating arm. By setting two rotating arms, the mutual positional relationship between the illumination unit and the image acquisition unit can be more flexibly adjusted, so that the image acquisition unit can be more quickly transformed into the required detection environment, thereby further improving the detection efficiency.

Preferably, the illumination unit of the present invention comprises a first light source and a second light source, the first light source is disposed on a fixed frame above the transfer unit, and the second light source is disposed on the first rotating arm . The arrangement of the two light sources makes the adjustment of the device of the invention more flexible and convenient, and can be adapted to various defect detection occasions and improve the application range.

Preferably, the image acquisition unit of the present invention is a first line camera, and the first line camera is disposed on a frame body below the transmission unit, and the detection is improved by using a high-resolution line array camera. Precision.

Preferably, the image acquisition unit of the present invention further includes a second line camera, and the second line camera is disposed on the second rotating arm. By providing a second line camera on the second rotating arm, the device of the present invention can be adjusted more flexibly and conveniently, and meet various defect simultaneous detection requirements.

Preferably, the rotation adjusting mechanism of the present invention is provided with a camera fine adjustment mechanism, and the camera fine adjustment mechanism is disposed on the second rotating arm. The camera can be fine-tuned by the camera fine-tuning mechanism to adjust the working distance between the image acquisition unit and the workpiece to be inspected, so that the image acquisition unit can collect clear images and improve the detection accuracy.

Preferably, the rotation adjusting mechanism of the present invention further comprises a dial, which are respectively disposed on the frame body on the left and right sides of the fixing frame. By setting the dials on both sides of the main body of the rack, the operator can be dynamically informed of the mutual positional relationship between the lighting unit and the image capturing unit, so that the operator can quickly adjust the lighting unit and the image collecting unit to the specific required. Angle, improved detection efficiency and detection accuracy.

Preferably, the conveying unit of the present invention is provided with a ball screw, a driving motor and a guide rail at the upper ends of the main body of the frame body, and the workpiece of the ball screw is provided with a workpiece jig, and the ball screw The screw is connected to the driving motor, and the rail is provided with a sliding seat, and the sliding seat is fixedly disposed at a lower end of the workpiece fixture. When in use, the workpiece to be inspected is placed on the workpiece fixture, and the driving motor drives the ball screw to rotate, and the workpiece to be inspected is moved from the front end of the device of the present invention to the detecting station.

Preferably, the workpiece fixture of the present invention comprises a fixture body, a support portion disposed on the fixture body, and a hollow portion penetrating up and down, the shape and size of the hollow portion matching the shape and size of the workpiece to be inspected, The support portion is formed by extending the fixture body toward the four corners of the hollow portion to support the workpiece to be inspected. The device of the invention can not only play the function of supporting the workpiece to be inspected but also the influence of the reflected light in the workpiece fixture by setting the support portion and the hollow portion penetrating up and down on the workpiece jig, and improving the detection precision.

An advantageous effect of the present invention is that the present invention is a machine vision-based glass defect detecting device, and since the present invention includes a rotation adjusting mechanism provided on a frame body, the illumination unit and the image capturing unit are disposed at the rotation adjustment Institutions, the rotation adjustment mechanism adjusts a mutual positional relationship between the illumination unit and the image acquisition unit, so that the image acquisition unit can perform light and dark field conversion according to detection requirements, thereby using the device of the present invention. By using the rotation adjustment mechanism, the mutual positional relationship between the illumination unit and the image acquisition unit can be conveniently and quickly adjusted, so that the image acquisition unit can perform bright and dark field changes according to the actual needs of the detection. A detection position integrates multiple lighting schemes, imaging lenses with different angles and line array cameras, successfully solves the problem of single defect detection, and can detect surface defects, internal defects and edge and side edge defects of the glass of the mobile phone cover. A variety of defect detection requirements to improve detection efficiency, can be applied to the pipeline For the case, while the apparatus of the present invention, high-resolution line camera and a very small imaging lens distortion, error rate, high precision and long time stability, saving a lot of labor resources, which greatly improves the work efficiency.

DRAWINGS

1 is a schematic structural view of an embodiment of a device of the present invention, and is a schematic view of a preferred embodiment.

2 is a schematic structural view of a main body of the frame of the present invention.

3 is a schematic structural view of a rotation adjusting mechanism of the present invention.

4 is a schematic structural view of an embodiment of a camera fine adjustment mechanism of the present invention.

FIG. 5 is a schematic structural view of a workpiece jig of the present invention.

Fig. 6 is a schematic view showing another structure of the workpiece jig of the present invention.

Detailed ways

The following description is presented to disclose the invention to enable those skilled in the art to practice the invention. The preferred embodiments in the following description are by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention as defined in the following description may be applied to other embodiments, modifications, improvements, equivalents, and other embodiments without departing from the spirit and scope of the invention.

1 to 6 are views showing the structure of an embodiment of the glass defect detecting device of the present invention, which is also a schematic view of a preferred embodiment. As shown in FIG. 1 and FIG. 2, the glass defect detecting apparatus according to the embodiment includes a rack main body 10, a transport unit 20, an illumination unit 30, an imaging unit 40, an image acquisition unit 50, a rotation adjustment mechanism 60, and a data processing unit. 70. The control unit 80, wherein the rack main body 10 is configured to carry components disposed thereon, and the transfer unit 20 is disposed at an upper end of the rack main body for transmitting a workpiece to be inspected, and is to be inspected The workpiece is sent to the inspection station by the loading worker, and the detected workpiece is sent to the unloading station by the inspection worker to realize automatic transmission detection and improve the detection efficiency. The illumination unit 30, the imaging unit 40 and the image acquisition unit 50 are respectively disposed on the frame body, and the illumination unit 30 is configured to provide illumination for defect detection, and the light emitted by the illumination unit 30 passes through the workpiece to be inspected. Entering the imaging unit 40 for imaging, the image acquisition unit 50 is connected to the imaging unit 40, the image acquisition unit 50 collects an image obtained by the imaging unit 40; the image acquisition unit 50 is connected to a data processing unit 70. The data processing unit performs a calculation process on the image collected by the image acquisition unit. The rotation adjustment mechanism 60 is disposed on the frame body 10, and the illumination unit and the image acquisition unit are disposed on the rotation adjustment mechanism, and the rotation adjustment mechanism collects the illumination unit and the image The mutual positional relationship between the units is adjusted, so that the image acquisition unit can perform bright and dark field transformation according to the detection needs, realize different detection modes, and flexibly respond to the operator's demand for different detection methods of various defects. For example, for the detection of the scratch on the surface of the cover glass of the mobile phone, the positive reflection bright field method can be used for detection, but for other defect detection, the operator may also need the positive reflection dark field mode detection, and by adjusting the rotation adjustment mechanism, It is convenient and effective to meet the needs of operators. The control unit is electrically connected to the transmitting unit, the image collecting unit, and the data processing unit, respectively, for performing work process control on the transmitting unit, the image collecting unit, and the data processing unit.

As a preferred embodiment, as shown in FIG. 3, the rotation adjusting mechanism 60 in the embodiment is provided with a fixing frame 61 and a rotating arm on the frame body, and the rotating arm is provided with at least one, and the rotating arm The swivel arm is capable of 360° continuous rotation. By setting the 360° rotation of the rotating arm, the mutual positional relationship between the illumination unit and the image acquisition unit can be conveniently and quickly adjusted, so that the image acquisition unit can perform bright and dark field changes according to the actual needs of the detection. Meet a variety of defect detection requirements and improve detection efficiency. Preferably, as can be seen from FIG. 3, the rotating arm in the present embodiment includes a first rotating arm 62 and a second rotating arm 63. By setting two rotating arms, the mutual positional relationship between the illumination unit and the image acquisition unit can be more flexibly adjusted, so that the image acquisition unit can be more quickly transformed into the required detection environment, thereby further improving the detection efficiency. Preferably, the rotation adjusting mechanism described in this embodiment further includes a dial 64 which is respectively disposed on the frame body 10 on the left and right sides of the fixing frame 61. By setting the dials on both sides of the main body of the rack, the operator can be dynamically informed of the mutual positional relationship between the lighting unit and the image capturing unit, so that the operator can quickly adjust the lighting unit and the image collecting unit to the specific required. Angle, improved detection efficiency and detection accuracy.

As a preferred embodiment, the illumination unit 30 in the embodiment includes a first light source 31 and a second light source 32. The first light source 31 is disposed on a fixed frame 61 above the transfer unit, and the second light source 32 It is disposed on the first rotating arm 62. The arrangement of the two light sources makes the adjustment of the device of the invention more flexible and convenient, and can be adapted to various defect detection occasions and improve the application range. Certainly, the illumination unit 30 may further include a third light source, a fourth light source, and the like. The number of the light sources may be added according to actual detection requirements, and the position of the light source may be flexibly exchanged on the fixed frame and the rotating arm according to actual needs. The invention is not limited.

As a preferred embodiment, the imaging unit 40 of the embodiment adopts an imaging lens with minimal distortion, the image acquisition unit 50 is a first line camera 51, and the first line camera is disposed under the transmission unit. On the main body of the rack, the detection accuracy is improved by using a high-resolution line array camera. Preferably, the image acquisition unit of this embodiment further includes a second line camera 52, and the second line camera is disposed on the second rotating arm. By providing a second line camera on the second rotating arm, the device of the present invention can be adjusted more flexibly and conveniently, and meet various defect simultaneous detection requirements. Of course, the image acquisition unit may further include a third line camera, a fourth line camera, and the like. The number of cameras may be added according to actual detection requirements, and the position of the camera may also be in the frame body and the rotating arm according to actual needs. The present invention is not limited in terms of flexible switching. It is worth mentioning that the front end of the camera is provided with an imaging lens.

As a preferred embodiment, the rotation adjustment mechanism 60 of the embodiment is provided with a camera fine adjustment mechanism 65. As shown in FIG. 1 and FIG. 4, the camera fine adjustment mechanism is disposed on the second rotation arm, and the imaging is performed. The lens and the camera are disposed on the camera fine adjustment mechanism. The camera fine-tuning mechanism can fine-tune the camera, adjust the working distance between the image acquisition unit and the workpiece to be inspected, so that the image acquisition unit can collect clear images and improve the detection accuracy.

As a preferred embodiment, the transport unit 20 of the embodiment is provided with a ball screw 21, a driving motor 22 and a guide rail 23 at the upper ends of the main body of the rack body, and the workpiece of the ball screw 21 is provided with a workpiece. The screw of the ball screw is connected to the driving motor, and the rail is provided with a sliding seat 25, and the sliding seat is fixedly disposed at a lower end of the workpiece fixture. When in use, the workpiece to be inspected is placed on the workpiece fixture, and the driving motor drives the ball screw to rotate, and the workpiece to be inspected is moved from the front end of the device of the present invention to the detecting station.

As a preferred embodiment, as shown in FIG. 5, the workpiece fixture 24 of the present embodiment includes a fixture body 240, and the fixture body is respectively provided with a sliding portion 241 in the length and width directions, and the sliding portion along the sliding portion The fixture body is moved forward and backward in the length and width directions, and the workpiece to be inspected is placed in a space formed by the sliding portion, and the fixture body 240 is made of a transparent material, preferably glass, and is used in use. The forward and backward movement of the sliding portion can fix the workpiece to be inspected in the space formed by the sliding portion, avoiding the displacement of the workpiece to be inspected during the conveying process, and improving the detection precision. More preferably, in order to avoid the influence of the fixture body on the detection accuracy, the present invention also provides another optimized workpiece fixture, such as the workpiece fixture shown in FIG. 6, including the fixture body 242 and the fixture body. a support portion 243 and a hollow portion 244 penetrating vertically, the shape of the hollow portion matching the shape and size of the workpiece to be inspected, wherein the support portion is extended toward the four corners of the edge of the hollow portion Formed to support the workpiece to be inspected. The workpiece fixture provided in the embodiment has a support portion and a hollow portion penetrating vertically, which can not only function to support the workpiece to be inspected, but also avoid the influence of reflected light in the workpiece fixture, thereby further improving the device of the present invention. Detection accuracy.

The data processing unit in this embodiment may be a general-purpose computer with data processing software, or a dedicated data processor, and the control unit is based on a programmable controller PLC (Programmable) The industrial computer of the Logic Controller is a mature technology in the prior art, and therefore will not be described here.

The detection process of the present invention is:

Open the main control program of the industrial computer, the machine returns to zero, and set the working parameters of the whole machine.

The industrial computer controls the driving motor to work. The driving motor drives the ball screw to rotate, so that the workpiece fixture is located within the field of view of the camera, and the calibration plate is placed at the position of the workpiece to be inspected, the lighting direction and the light source intensity are adjusted, and the camera fine-tuning structure is fine-tuned. The lens is at its working distance. Then, the camera is corrected for light and dark fields, and the calibration result is imported into the camera and the relevant operating parameters such as exposure time and aperture are set.

The industrial control mechanism controls the driving motor to work, the driving motor drives the ball screw to rotate, so that the workpiece jig is located at the loading station, and the workpiece to be inspected is placed and fixed, such as the mobile phone cover glass, and the workpiece moving speed and camera image collection are set on the industrial computer. starting point.

Each rotating arm of the rotation adjusting mechanism is adjusted so that the positional relationship of each light source and the camera conforms to the lighting mode of the specific defect to be inspected.

The driving motor drives the workpiece to move, so that the workpiece to be inspected passes through the field of view of the line camera under the driving of the workpiece fixture. At this time, the encoder signal of the driving motor will also inform the camera of the image acquisition frequency through the main program, ensuring The running speed of the workpiece to be inspected is consistent with the image acquisition speed of the camera.

After the camera performs image acquisition, the data is sent to the data processing unit through the image acquisition card for analysis and the defect type, size and position are determined.

Those skilled in the art should understand that the embodiments of the present invention described in the above description and the accompanying drawings are only by way of illustration and not limitation. The object of the invention has been achieved completely and efficiently. The present invention has been shown and described with respect to the embodiments of the present invention, and the embodiments of the present invention may be modified or modified without departing from the principles.

Claims

A glass defect detecting device, comprising:

a frame body for carrying a component disposed thereon;

a conveying unit disposed at an upper end of the frame body for conveying the workpiece to be inspected;

a lighting unit disposed on the frame body for providing illumination for defect detection;

An imaging unit, the light emitted by the illumination unit passes through the image to be inspected and enters the imaging unit for imaging;

An image acquisition unit that connects the imaging unit and acquires an image obtained by the imaging unit;

a data processing unit, connected to the image acquisition unit, and performing calculation processing on the image collected by the image acquisition unit;

a rotation adjustment mechanism disposed on the frame body, the illumination unit and the image acquisition unit being disposed on the rotation adjustment mechanism, the rotation adjustment mechanism being between the illumination unit and the image acquisition unit The mutual positional relationship is adjusted to enable the image acquisition unit to perform bright and dark field transformation according to the detection needs;

The control unit is electrically connected to the transmitting unit, the image collecting unit, and the data processing unit, respectively.
The glass defect detecting device according to claim 1, wherein the rotation adjusting mechanism is provided with a fixing frame and a rotating arm on the frame body, the rotating arm is provided with at least one, and the rotation The arm can be rotated 360° continuously.
The glass defect detecting apparatus according to claim 2, wherein the rotating arm comprises a first rotating arm and a second rotating arm.
The glass defect detecting apparatus according to claim 3, wherein the illumination unit comprises a first light source and a second light source, the first light source is disposed on a fixed frame above the transfer unit, and the second A light source is disposed on the first rotating arm.
The glass defect detecting apparatus according to claim 3 or 4, wherein said image capturing unit is a first line camera, and said first line camera is disposed on a frame body below said conveying unit .
The glass defect detecting apparatus according to claim 5, wherein said image capturing unit further comprises a second line camera, and said second line camera is disposed on said second rotating arm.
The glass defect detecting apparatus according to claim 1 or 2 or 3 or 4, wherein said rotation adjusting mechanism is provided with a camera fine adjustment mechanism.
The glass defect detecting device according to claim 2 or 3 or 4, wherein the rotation adjusting mechanism further comprises a dial, and the dials are respectively disposed on the frame body on the left and right sides of the fixing frame .
The glass defect detecting device according to claim 1 or 2 or 3 or 4, wherein the conveying unit is provided with a ball screw, a driving motor and a guide rail at upper ends of the main body of the frame body, the ball A workpiece fixture is disposed on the nut of the screw rod, and the screw of the ball screw is connected to the driving motor, and the rail is provided with a sliding seat, and the sliding seat is fixedly disposed at a lower end of the workpiece fixture.
The glass defect detecting device according to claim 9, wherein the workpiece jig includes a jig body, a support portion provided on the jig body, and a hollow portion penetrating vertically, the shape and size of the hollow portion The support portion is formed by extending the jig body toward the four corners of the hollow portion to support the workpiece to be inspected.