CN213715092U

CN213715092U - Aluminum foil paper surface defect detection device

Info

Publication number: CN213715092U
Application number: CN202022724190.5U
Authority: CN
Inventors: 袁俊杰; 张超强; 赵倩倩; 戴宜全
Original assignee: Changzhou College of Information Technology CCIT
Current assignee: Changzhou College of Information Technology CCIT
Priority date: 2020-11-23
Filing date: 2020-11-23
Publication date: 2021-07-16
Anticipated expiration: 2030-11-23

Abstract

The utility model provides an aluminium foil paper surface defect detection device constructs the structured light of suitable slope and projection specific wavelength, and the reverberation is formed images by the camera on arriving purpose-made mute light screen board. The image obtained under the ideal condition is also a stripe image, the reflected light of the image is correspondingly influenced when a defect exists, if only one detection point is seen, the aluminum foil is driven to advance along with the rotation of the roller, and then one point on the detection object is irradiated and reflected by light with different brightness, which is different from the fixed light intensity adopted in the background technology and is more advantageous; if the whole image is seen, analyzing the stripe image of the whole surface; the stripes are regular patterns and the defects are disturbances therein, so the solution of the invention makes it easier to find the defects by contrast.

Description

Aluminum foil paper surface defect detection device

Technical Field

The utility model relates to a defect detection field especially relates to an aluminium foil paper surface defect detection device.

Background

The aluminum foil paper is generally formed by rolling thin aluminum plates for multiple times, is mainly used for packaging food and medicines with high requirements on bacteria isolation, and can seriously affect the experience of consumers due to appearance defects. The production of the aluminum foil mainly depends on a rolling mill, and no special cleaning requirement is required for the field environment, so that oil stains, pockmarks, micropores, scratches and the like are common defects in the rolling process.

The aluminum foil has a high-reflection surface, so that the corresponding pixel value of an image is easily oversaturated, and the aluminum foil is a difficulty for implementing machine vision defect detection. To address this problem, CN201621098098 (an illumination light source for inspecting a highly reflective surface) is a light source specifically designed for highly reflective surface defect inspection, but is not suitable for inspecting an inspection object in a long roll shape such as an aluminum foil in terms of its configuration; CN201821191899 (detection device for surface flaws of high-reflection cylindrical parts) mainly detects flaws by observing the change of the reflection line of a line laser incident on the surface of a workpiece on a receiving screen. In combination with the paper "application of laser to surface flaw detection of high-reverse-surface shaft parts", which is published in the journal of "laser and infrared" by the same author, the measurement object is a battery case with a small volume. The detection mechanism is feasible, but the paper shows that the effect is to be further studied, e.g. the reflected line is not a straight line and the scratch is only reflected in the notch of the reflected line. CN201910683968 (a defect detection apparatus and detection method) sequentially lights light sources in different directions and takes a picture, and obtains an image without the influence of high reflection light by fusing a plurality of collected images. On the one hand, the processing speed is slow, and on the other hand, the fusion algorithm and the stability are questionable. CN201780033749 (surface inspection system and inspection method) irradiates the surface of a workpiece with two incident rays having different angles with a surface to be inspected, and images the reflected rays with a camera on the object plane normal symmetry side. Essentially, the imaging is carried out under the conditions of bright field illumination and dark field illumination, and the premise of actually observing the scratch is that incident light vertically irradiates on the scratch and forms a proper angle with the object surface, so that the reflected light can be ensured to enter a camera, and the effect that the bright pixels are distributed on the scratch and other positions are respectively dark pixels is realized. There are also enterprises in the market that develop machine vision products for defect detection of aluminum foil paper, such as the tin-free fine vision company, which is known from introduction of official website and patents inquired by the enterprise (CN 201920576275, a device for detecting pinholes on the surface of aluminum foil), and mainly aims at detection of pinholes.

It is therefore important to solve the above problems.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model provides an aluminium foil paper surface defect detection device constructs the structured light of suitable slope and projection specific wavelength, and the reverberation is formed images by the camera on arriving purpose-made mute light screen board. The image obtained under the ideal condition is also a stripe image, the reflected light of the image is correspondingly influenced when a defect exists, if only one detection point is seen, the aluminum foil is driven to advance along with the rotation of the roller, and then one point on the detection object is irradiated and reflected by light with different brightness, which is different from the fixed light intensity adopted in the background technology and is more advantageous; if the whole image is seen, analyzing the stripe image of the whole surface; the stripes are regular patterns and the defects are disturbances therein, so the solution of the invention makes it easier to find the defects by contrast.

The utility model aims at providing an aluminum foil paper surface defect detection device, which comprises a first roller, a second roller and a third roller which are arranged at the left, the middle and the right sides, wherein the bottom of each roller is movably connected with a supporting rod with adjustable height, and the bottom of the supporting rod is provided with a ground foot fixing device which is fixed on the ground; the front side and the rear side above the second roller and the third roller are respectively provided with a first inner matte surface light screen, the right side of the first three inner matte surface light screens is provided with a second vertical inner matte surface light screen, the four light screens cover and surround the first inner matte surface light screens, and a structured light projector is arranged on the lower left part of the top inner matte surface light screen and is positioned above the second roller and the third roller; a flat matte surface screen plate with a matte surface on the upper surface is arranged above the third roller, the matte surface screen plate is positioned at the right lower part of the structured light projector, and the right end of the matte surface screen plate is connected with the inner matte surface light screen II; a camera telescopic rod is arranged at the bottom of the inner matte surface light screen plate at the top and above the matte surface screen plate, and a camera with a lens at the bottom is arranged at the bottom of the camera telescopic rod; the aluminum foil paper is fed from the bottom of the first roller, passes through the top of the second roller and is discharged from the bottom of the third roller.

The further improvement lies in that: the first roller is used for downwards orienting the strip-shaped aluminum foil output by the rolling mill, the second roller is used for upwards orienting the aluminum foil, the third roller and the second roller have certain height difference and certain distance, the aluminum foil is enabled to generate certain slope between the second roller and the third roller, and the slope can be adjusted by adjusting the position of the rollers so as to adapt to the requirement of subsequent polishing.

The further improvement lies in that: the structured light projector is arranged above the second roller and the third roller, the front position and the back position of the structured light projector are adjustable, the height of the structured light projector and the angle of transmission to the inclined plane of the aluminum foil are adjustable, the structured light projector is used for downwards transmitting laser stripes to the surface of the aluminum foil below, and the laser stripes reach the upper surface of the screen plate with the matte surface after being reflected by the aluminum foil.

The further improvement lies in that: the camera is adhered with a band-pass filter film or a front filter aiming at laser wavelength on an imaging target surface of the camera as an accessory, a polaroid is arranged at the front end of a lens as the accessory, and the polarization direction is adjusted to a proper angle on the basis of reducing strong reflection when the camera is used; the camera and the lens are arranged together above the matte surface screen plate to image the stripes on the upper surface of the matte surface screen plate.

The further improvement lies in that: the system also comprises a software control module used for realizing image acquisition, image defect analysis and acousto-optic alarm control; the method adopts a conventional method in the field of fringe analysis or signal processing, and aims at the jitter in the transmission process, and the processing method comprises the following steps: continuously recording and dynamically keeping a plurality of images (> 20), tracking the change of the gray value of each pixel point in the front and back images, and enabling the signal camera speed of the change to be a signal with one-dimensional regular change to be fast enough relative to aluminum foil transmission, and destroying the regularity of the change when a defect exists.

The further improvement lies in that: the camera and the structured light projector are parallel and at least one of the camera and the structured light projector is arranged; for the case of a wider aluminum foil strip, a plurality of projectors and cameras are arranged in parallel.

The utility model also provides a method for detecting the surface defects of the aluminum foil paper, the structured light projector projects laser stripes with specific wavelength to the aluminum foil inclined plane, the laser stripes are reflected by the aluminum foil inclined plane to reach the specially manufactured matte surface screen plate so as to be convenient for imaging, a camera is used for shooting and imaging the reflected light on the matte surface screen plate, and a regular stripe pattern is obtained when no defects exist; when a defect exists, the reflection of light at the defect is influenced, and then interference is formed in the collected image; the regular stripes can be regarded as carrier waves in nature, can be removed through demodulation, and can be easily analyzed through contrast analysis.

The utility model has the advantages that: the utility model transmits the aluminum foil belt to be detected to the rear end under the driving of the first roller, the second roller and the third roller, the height and the position of the three rollers can be adjusted, and particularly, a proper inclined plane to be detected is constructed by adjusting the distance and the height difference between the second roller and the third roller; the structured light projector with adjustable position and projection angle transmits laser stripes with specific wavelength to an inclined plane to be detected, the laser stripes reach a matte surface screen plate at the lower right part through the reflection of the inclined plane, a camera, a lens and accessories thereof are arranged above the matte surface screen plate through a camera telescopic rod, and a camera imaging target surface is adhered with a band-pass filter film or a front filter as accessories for the laser; the front of the lens is provided with a polaroid as an accessory, and the polarization direction is adjusted by taking reduction of image supersaturation as a standard when the lens is used. In order to reduce the influence of stray light, an inner matte surface light shielding plate II and an inner matte surface light shielding plate I are used for surrounding above and on the side surface of the second roller, the third roller and the matte surface light shielding plate.

When the aluminum foil strip is used, the aluminum foil strip is driven by the roller to move towards the rear end, the camera shoots a reflected stripe image, and a regular stripe image is obtained under the condition of no defect; when defective, the defect will change the corresponding laser reflection.

The utility model discloses construct the structured light of suitable slope and the specific wavelength of projection, the reverberation is formed images by the camera on arriving purpose-made matte screen board. The image obtained under the ideal condition is also a stripe image, the reflected light of the image is correspondingly influenced when a defect exists, if only one detection point is seen, the aluminum foil is driven to advance along with the rotation of the roller, and then one point on the detection object is irradiated and reflected by light with different brightness, which is different from the fixed light intensity adopted in the background technology and is more advantageous; if the whole image is seen, analyzing the stripe image of the whole surface; the stripes are regular patterns and the defects are disturbances therein, so the solution of the invention makes it easier to find the defects by contrast.

Drawings

Fig. 1 is a schematic diagram of the present invention.

Wherein: 1-a camera telescopic rod, 2-a camera, 3-a lens, 4-, a structured light projector, 5-a matte surface screen plate, 6-an inner matte surface screen plate II, 7-an inner matte surface screen plate I, 8-1-a first roller, 8-2-a second roller, 8-3-a third transmission roller, 9-an aluminum foil belt, 10-1, 10-2, 10-3, 10-4-supporting rods, 11-1, 11-2, 11-3 and 11-4-anchor fixing devices.

Detailed Description

In order to deepen the understanding of the present invention, the present invention will be described in detail with reference to the following embodiments, which are only used for explaining the present invention and do not limit the protection scope of the present invention.

As shown in fig. 1, the embodiment provides a device for detecting surface defects of aluminum foil paper, which includes a first roller 8-1, a second roller 8-2 and a third roller 8-3, which are arranged at the left, middle and right sides, wherein the bottom of each roller is movably connected with a supporting rod with adjustable height, and the bottom of each supporting rod is provided with a foot fixing device fixed on the ground; the front side and the rear side above the second roller 8-2 and the third roller 8-3 are respectively provided with a first inner matte surface light shielding plate 7, the right sides of the first three inner matte surface light shielding plates 7 are provided with a second vertical inner matte surface light shielding plate 6, the four light shielding plates cover and surround, a structured light projector 4 is arranged on the left part below the first top inner matte surface light shielding plate 7, and the structured light projector 4 is positioned above the second roller 8-2 and the third roller 8-3; a flat matte surface screen plate 5 with a matte surface on the upper surface is arranged above the third roller 8-3, the matte surface screen plate 5 is positioned at the right lower part of the structured light projector 4, and the right end of the matte surface screen plate is connected with the inner matte surface screen plate II 6; the bottom of the inner matte surface light screen I7 at the top is positioned above the matte surface screen plate 5 and is provided with a camera telescopic rod 1, and the bottom of the camera telescopic rod 1 is provided with a camera 2 with a lens 3 at the bottom; the aluminum foil paper is fed from the bottom of the first roller 8-1, passes through the top of the second roller 8-2 and is discharged from the bottom of the third roller 8-3.

The first roller 8-1 orients the strip aluminum foil produced by the rolling mill downwards, the second roller 8-2 orients the aluminum foil upwards, the third roller 8-3 and the second roller 8-2 have certain height difference and certain distance, and then the aluminum foil generates certain slope between the second roller 8-2 and the third roller 8-3, and the slope can be adjusted by adjusting the position of the rollers to meet the requirement of subsequent polishing.

The structured light projector 4 is a structured light projector with a specific wavelength, is arranged above the second roller 8-2 and the third roller 8-3, and has adjustable front and back positions, height and angle of transmission to the inclined plane of the aluminum foil, so as to downwards emit laser stripes to the surface of the aluminum foil below, and reach the upper surface of the matte surface screen plate 5 after being reflected by the aluminum foil.

A band-pass filter film or a front filter aiming at laser wavelength is adhered on the imaging target surface of the camera 2 to serve as an accessory, a polaroid is arranged at the front end of the lens 3 to serve as the accessory, and the polarization direction is adjusted to a proper angle by taking strong reflection reduction as a criterion when the camera is used; the camera 2 and lens 3 are arranged in combination above the matte-surface screen panel 5 to image the stripes on its upper surface.

The system also comprises a software control module used for realizing image acquisition, image defect analysis and acousto-optic alarm control; the method adopts a conventional method in the field of fringe analysis or signal processing, and aims at the jitter in the transmission process, and the processing method comprises the following steps: continuously recording and dynamically keeping a plurality of images to be more than 20, tracking the change of the gray value of each pixel point in the front and back images, and enabling the signal camera which is one-dimensional regularly changed to have a speed which is fast enough relative to aluminum foil transmission, and destroying the regularity when a defect exists.

The embodiment also provides a method for detecting the surface defects of the aluminum foil paper, a structured light projector 4 projects laser stripes with specific wavelength to an aluminum foil inclined plane, the laser stripes are reflected by the aluminum foil inclined plane to reach a specially manufactured matte surface screen plate 5 to facilitate imaging, a camera 2 is used for shooting and imaging the reflected light on the matte surface screen plate 5, and a regular stripe pattern is obtained when no defect exists; when a defect exists, the reflection of light at the defect is influenced, and then interference is formed in the collected image; the regular stripes can be regarded as carrier waves in nature, can be removed through demodulation, and can be easily analyzed through contrast analysis.

The aluminum foil strip to be detected is driven by a first roller 8-1, a second roller 8-2 and a third roller 8-3 to be transmitted to the rear end, the heights and the positions of the three rollers are adjustable, and particularly, a proper inclined plane to be detected is constructed by adjusting the distance and the height difference between the second roller 8-2 and the third roller; the structured light projector 4 with adjustable position and projection angle transmits laser stripes with specific wavelength to an inclined plane to be detected, the laser stripes reach a matte surface screen plate 5 at the lower right part through the reflection of the inclined plane, a camera, a lens and accessories of the camera are arranged above the matte surface screen plate 5 through a camera telescopic rod, and a band-pass filter film or a front filter for the laser is adhered to the imaging target surface of the camera to serve as the accessories of the camera; the front of the lens is provided with a polaroid as an accessory, and the polarization direction is adjusted by taking reduction of image supersaturation as a standard when the lens is used. In order to reduce the influence of stray light, an inner matte surface light shielding plate two 6 and an inner matte surface light shielding plate one 7 are used for surrounding above and on the side surface of the second roller 8-1, the third roller 8-2 and the matte surface screen plate 5.

When the device is used, the aluminum foil strip is driven by the roller to move towards the rear end, the camera 2 shoots a reflected stripe image, and a regular stripe image is obtained under the condition of no defect; when defective, the defect will change the corresponding laser reflection.

Claims

1. The utility model provides an aluminium foil paper surface defect detection device which characterized in that: the device comprises a first roller (8-1), a second roller (8-2) and a third roller (8-3) which are arranged at the left, middle and right sides, wherein the bottom of each roller is movably connected with a supporting rod with adjustable height, and the bottom of each supporting rod is provided with a ground foot fixing device fixed on the ground; inner matte surface light shielding plates I (7) are arranged on the front side and the rear side above the second roller (8-2) and the third roller (8-3), vertical inner matte surface light shielding plates II (6) are arranged on the right sides of the three inner matte surface light shielding plates I (7), the four light shielding plates are covered and surrounded, a structured light projector (4) is arranged on the left part below the inner matte surface light shielding plate I (7) on the top, and the structured light projector (4) is positioned above the second roller (8-2) and the third roller (8-3); a flat matte surface screen plate (5) with a matte surface on the upper surface is arranged above the third roller (8-3), the matte surface screen plate (5) is positioned at the right lower part of the structured light projector (4), and the right end of the matte surface screen plate is connected with the inner matte surface light screen plate II (6); a camera telescopic rod (1) is arranged at the bottom of the inner matte surface light screen I (7) at the top and above the matte surface screen plate (5), and a camera (2) with a lens (3) at the bottom is arranged at the bottom of the camera telescopic rod (1); the aluminum foil paper is fed from the bottom of the first roller (8-1), passes through the top of the second roller (8-2) and is discharged from the bottom of the third roller (8-3).

2. The apparatus for detecting surface defects of aluminum-foil paper as claimed in claim 1, wherein: the first roller (8-1) orients the strip aluminum foil produced by the rolling mill downwards, the second roller (8-2) orients the aluminum foil upwards, the third roller (8-3) and the second roller (8-2) have certain height difference and certain distance, and then the aluminum foil generates certain slope between the second roller (8-2) and the third roller (8-3), and the slope can be adjusted by adjusting the position of the rollers to adapt to the requirement of subsequent polishing.

3. The apparatus for detecting surface defects of aluminum-foil paper as claimed in claim 1, wherein: the structured light projector (4) is a structured light projector with a specific wavelength, is arranged above the second roller (8-2) and the third roller (8-3), and has adjustable front and back positions, height and angle of transmitting to the aluminum foil inclined plane, so as to downwards emit laser stripes to the lower aluminum foil surface, and reach the upper surface of the matte surface screen plate (5) after being reflected by the aluminum foil.

4. The apparatus for detecting surface defects of aluminum-foil paper as claimed in claim 1, wherein: a band-pass filter film or a front filter aiming at laser wavelength is adhered on the imaging target surface of the camera (2) to serve as an accessory, a polaroid is arranged at the front end of the lens (3) to serve as the accessory, and the polarization direction is adjusted to a proper angle by taking strong reflection reduction as a criterion during use; the camera (2) and the lens (3) are combined and arranged above the matte surface screen plate (5) to image the stripes on the upper surface of the matte surface screen plate.

5. The aluminum-foil paper surface defect detecting device of claim 1, wherein: the system also comprises a software control module used for realizing image acquisition, image defect analysis and acousto-optic alarm control.

6. The apparatus for detecting surface defects of aluminum-foil paper as claimed in claim 1, wherein: the camera (2) and the structured light projector (4) are arranged in parallel and at least one of the camera and the structured light projector is arranged.