JP2000338046A - Foreign matter removing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remove foreign matter such as stones or ceramics in recycled glass cullet with high accuracy by simple constitution. SOLUTION: Glass cullet is charged in a hopper 1 collectively to be supplied to a conveyor 2 by small quantity so that cullet pieces K do not overlap each other. The cullet pieces K are carried on the conveyor 2 to fly out from the end part of the conveyor. At this time, the cullet pieces K are irradiated with measuring light from a visible/ultraviolet light source 3 to perform penetrative photographing at the same time by a visible camera 5 and an ultraviolet camera 6. When the cullet pieces K are glass pieces, since glass permits visible light to transmit but does not almost permit ultraviolet rays to transmit, images at a time of penetrative photographing by visible light and ultraviolet rays do not coincide with each other. Since ceramics or stones do not permit both of visible light and ultraviolet rays to transmit, images at a time of penetrative photographing by visible light and ultraviolet rays coincide with each other. Therefore, if two penetrative photographing images do not coincide with each other, glass (target article) is judged and, if coincide, the presence of foreign matter is judged and this foreign matter is blown off by an air nozzle 9 to be classified and removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for automatically removing foreign substances such as plastic pieces, stones, and ceramic pieces in crushed pieces (glass cullet) in, for example, glass recycling. It is.

[0002]

2. Description of the Related Art In various fields, it is desired to remove foreign substances other than the target object from many objects.
In particular, in recent years, from the standpoint of recycling, there is a high technical demand for a foreign matter removing apparatus for crushing collected waste glass bottles and the like into small pieces (glass cullets) and using them as raw materials for regeneration.

[0003] Waste glass to be collected and collected contains a cap made of synthetic resin, aluminum, or cork, a ceramic bottle, and other foreign substances. When these are crushed and used as cullet as they are, due to the presence of these foreign substances, undissolved substances are formed in the glass reclaimed product, the color tone and clarity of the product are changed, bubbles are generated, It impairs strength and aesthetics and reduces product value. Therefore, there is an increasing technical demand for removing foreign matter other than glass as accurately and strictly as possible at the cullet stage.

In general, cullets finely crushed by a crushing device or the like are mixed in a single layer by a conveying means such as a belt conveyor or the like, and mixed therewith, aluminum pieces crushed together with a glass bottle,
Foreign material pieces such as plastic pieces, pottery pieces, and stones are automatically determined by visual inspection by an operator or by the light transmittance of the measurement light, and are removed by hand picking, suction, or the like.

[0005]

In the method of visual judgment by the worker, it goes without saying that the burden on the worker becomes extremely large, and foreign matters are missed due to the eyestrain of the worker and lack of attention. Cannot be maintained. There were also problems from the viewpoint of automation and labor saving. On the other hand, in the case of automatic determination by a machine, a method of irradiating each cullet piece with measurement light and determining whether the cullet piece is a glass piece or other foreign matter by a technique of determining whether or not the measurement light is sufficiently transmitted. However, when the foreign matter pieces are small, they do not block the light sufficiently, so erroneous judgment occurs and foreign matter is not removed,
As described above, the quality of the recycled product is deteriorated. Conversely, even if a glass piece does not enter the light receiving side due to refraction of light or the like, it is determined to be a foreign substance, and resources are not effectively used. Similarly, even when a label, a sticker, or the like remains on the glass piece, the light does not pass through and is determined to be a foreign substance. Similarly, when the glass piece is dirty and the light transmittance is low, it is erroneously determined to be a foreign substance, and a sufficient resource waste recovery rate cannot be obtained.
Actually, no automatic judgment is actually performed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a foreign matter removing apparatus capable of accurately determining and removing only foreign matter from any small piece.

[0007]

Means for Solving the Problems To solve the above problems, a foreign matter removing apparatus according to the present invention is configured as follows.

A first foreign matter removing apparatus according to the present invention comprises: a measuring light irradiating means for irradiating an object with visible light and ultraviolet light; a transmitted light measuring means for measuring a transmitted light from the object;
Determining means for automatically determining whether the object is an object or a foreign object from the difference between the measurement results of visible light and ultraviolet light by the transmitted light measuring means, and an object based on the determination result of the determining means And a separating means for automatically separating the foreign matter from the foreign matter.

A second foreign matter removing apparatus according to the present invention comprises: a measuring light irradiating means for irradiating a measuring light to an object; a transmitted light image measuring camera for measuring a transmitted light from the object; The inside of the outline of the transmitted light image of the object is divided and recognized as pixels, and when the number of pixels indicating the amount of transmitted light corresponding to a predetermined range falls outside the predetermined pixel number range, the target object is regarded as a foreign object. It comprises a determining means for determining, and a separating means for automatically separating the target object and the foreign matter based on the determination result of the determining means.

A third foreign matter removing apparatus according to the present invention comprises: a measuring light irradiating means for irradiating a measuring light to an object; a transmitted light image measuring camera for measuring a transmitted light from the object; Determining means for dividing and recognizing the inside of the outline of the transmitted light image of the object as a pixel, and determining the object as a foreign object when the difference in the amount of transmitted light between any two pixels does not fall within a preset range; A separating means for automatically separating the object and the foreign matter based on the determination result of the determining means.

A fourth foreign matter removing apparatus according to the present invention comprises: a measuring light irradiating means for irradiating a measuring light to an object; a transmitted light image measuring camera for measuring a transmitted light from the object; When the inside of the outline of the transmitted light image of the object is divided and recognized as pixels, and the number of times when the difference in the amount of transmitted light among a plurality of pixels falls within a preset range is not within the preset number range, Determining means for determining that the object is a foreign matter; and separating means for automatically separating the target object and the foreign matter based on the determination result of the determining means.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a foreign matter removing apparatus according to the present invention will be described with reference to an example of removing foreign matter in a crushed glass bottle cullet in glass recycling. The practice of the present invention is not limited to glass recycling, but means suitable for utilizing the optical property difference between the target object and foreign matter, such as waste resin, metal, ceramics, cork, stone, paper, and living body. Therefore, it is needless to say that it can be appropriately used regardless of the size of the sample.

In the case of glass recycling, a discarded and collected glass bottle is subjected to a treatment for removing a label or the like, and then finely broken into small pieces to form a glass cullet. In this cullet, there are bottle caps and pebbles made of resin, cork, etc.
A metal piece such as a pull-top of a beverage can or the like is mixed as a foreign substance, and some of the glass pieces have a label that remains partially adhered without being completely removed, and some have a stain.

FIG. 1 shows a first configuration example of a foreign matter removing apparatus according to the present invention. Glass cullet as described above is hopper 1
The cullet pieces are supplied onto the conveyor 2 one by one so that the cullet pieces do not overlap. The cullet piece K is carried on the conveyor 2 and jumps out from the end of the conveyor. At this time, it is desirable that the conveyor 2 be operated horizontally and at a constant speed in order to improve the image quality during transmission shooting described later and to keep the timing of foreign matter removal constant. Jump out at more constant timing. When the cullet piece K protrudes from the end of the conveyor, measurement light is emitted from the visible / ultraviolet light source 3, and the visible light camera 5 and the ultraviolet light camera 6 simultaneously perform transmissive imaging via the half mirror 4.

When the measured cullet piece K is a glass piece (object), the glass transmits visible light but hardly transmits ultraviolet light. Images do not match. Even in the case where the label remains unremoved or stains adhere to the glass piece, it is considered that it is unlikely that the label remains evenly on the entire surface of the glass piece. The captured images do not match. On the other hand, since ceramics and stone do not transmit both visible light and ultraviolet light, the transmitted and captured images of visible light and ultraviolet light match. Therefore, if the transmitted and captured images of visible light and ultraviolet light do not match, it can be determined that the object is glass (object), and if they match, it is a foreign object.

Now, the two captured images are combined into one image by the image combining device 7. The composition is performed by an EX-OR (exclusive OR) technique. The synthesized image is as shown in FIG.

According to such image processing, when both visible and ultraviolet images do not match, that is, when a synthetic image is made of glass, it is expressed in black, while when the images match like foreign matter, Expressed whitish. The image synthesized in this way is input to the determination circuit 8, and if the image is a black image having an area equal to or larger than a predetermined threshold value, the cullet piece is determined to be glass, and the others are determined to be foreign substances.

The cullet piece K determined to be "foreign matter" by the determination circuit 8 is blown off from the parabola by the air nozzle 9 and is separated from the glass piece by dropping into the foreign matter receiver.

Although a visible / ultraviolet camera is used in this embodiment, a photoelectric conversion element such as a silicon photodiode is used in place of the camera, and the absolute value of the output difference between visible / ultraviolet is set to a predetermined threshold value. It is also possible to make a foreign matter determination based on whether or not it exceeds.

It is of course possible to provide a plurality of such discriminating means and discriminating means such as air nozzles so that a large amount of foreign matter can be removed at a time.

Next, another embodiment of the present invention is shown in FIG. Components common to those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. The image of the cullet piece K protruding from the conveyor 2 is detected by the preprocessing device 12 to be converted into an image in which the outline is enhanced, and is divided and recognized in pixel units. FIG. 4 shows an image example at this time.

These images are input to the judgment circuit 8, and the judgment method is appropriately selected from the following in accordance with the required accuracy and processing speed.

The first judgment method is a method of judging that even if there is at least one pixel having a transmitted light amount equal to or more than a predetermined threshold value inside the outline of the cullet piece image, this is determined to be glass. In the conventional method, judgment was made based on the entire transmitted light amount.Thus, even if the measuring piece was glass, the transmitted light amount was insufficient depending on the degree of contamination and the remaining state of the label, and it was determined that the particle was a foreign substance. However, if there is a transmissive portion, it can be determined as glass. In the sample of FIG. 4, is determined to be glass, and the others are determined to be foreign matter.

In a second determination method, if the number of pixels showing a transmitted light amount equal to or greater than a predetermined threshold value inside the outline of the cullet piece image is larger than a predetermined number, this is determined as glass. Is the way. In the first determination method, a stone, metal, or the like having a hole has a transmission portion, which causes an erroneous determination. However, according to the present method, a correct determination can be made even in such a case. In the sample shown in FIG. 4, when the threshold value is set so that five or more white pixels are determined to be glass, glass is determined to be glass, and the others are determined to be foreign matter.

A third determination method is a method of determining that the glass is glass when the difference in the amount of transmitted light between any two pixels inside the outline of the cullet piece image is larger than a preset value. is there. In this method, it is possible to discriminate between a label such as porcelain and plastic that transmits a small amount of light and a glass with a label or stain. Figure 4
In the sample No., only the one having a large difference in the amount of transmitted light between pixels is determined to be glass, so that is determined to be glass, and the others are determined to be foreign substances.

In the fourth determination method, the difference in the amount of transmitted light between any two pixels inside the outline of the cullet piece image is examined. This is also examined among other plural pixels, and glass is used only when the number of times the difference in the amount of transmitted light is larger than a predetermined value is equal to or more than a predetermined number of times, as in the third determination method. This is a method for determining whether or not a higher accuracy is required than the third determination method. In the sample of FIG. 4, is determined to be glass, and the others are determined to be foreign substances.

The cullet piece K determined as "foreign matter" in the determination circuit 8 by such a method is blown off from the parabola by the air nozzle 9 and is separated from the glass piece.

The method of sorting is not limited to blowing off with an air nozzle, but may be performed by a robot hand,
It is sufficient that only foreign matter is separated by a known technique such as a scraping valve and suction removal.

It is not always necessary to convey by a conveyor, and a design change can be made as appropriate, such as a method of sliding on a slope or a batch processing method in which the object to be measured is replaced every time instead of a continuous conveyance method. Alternate configurations of other components are also possible within the scope of known techniques.

[0030]

As described above, according to the foreign matter removing apparatus according to the present invention, the accuracy of foreign matter determination can be significantly improved as compared with the conventional method. In addition, the rate of foreign matter removal can be greatly increased by reducing missed particles, and at the same time, the rate of foreign matter mixed into the processed cullet can be reduced, thereby improving the quality of the recycled product and increasing the commercial value. As a result, it can also contribute to improving the recovery rate of resource waste.

Since the foreign matter removing apparatus according to the present invention employs a foreign matter determining method using not only the amount of transmitted light but also image processing, the accuracy of determination is improved, and the material, shape, and size of the object and foreign matter are of course improved. It is possible to cope with various situations irrespective of specific gravity, mass, and the like, and there is no need to change the configuration every time.

When a discrimination method utilizing a difference between visible / ultraviolet transmission images is employed, complicated software processing is not required, so that an inexpensive and high-speed foreign substance removing apparatus can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration example of a foreign matter removing device according to the present invention.

FIG. 2 is a diagram showing an example of image processing of the foreign matter removing device according to the present invention.

FIG. 3 is a diagram illustrating another configuration example of the foreign matter removing device according to the present invention.

FIG. 4 is a diagram showing an example of image processing of the foreign matter removing device according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 Hopper 2 Conveyor 3 Measurement light source 4 Half mirror 5 Camera for visible light 6 Camera for ultraviolet light 7 Image synthesizing device 8 Judgment circuit 9 Air nozzle 12 Pretreatment device K

Claims (4)

[Claims] 1. A measuring light irradiating means for irradiating an object with visible light and ultraviolet light, a transmitted light measuring means for measuring transmitted light from the object, and a visible light and an ultraviolet light by the transmitted light measuring means. Determining means for automatically determining whether the target is a target or a foreign substance from the difference in the measurement results, and separating means for automatically separating the target and the foreign substance based on the determination result of the determining means. Foreign matter removing device. 2. A measuring light irradiating means for irradiating measuring light to an object, a transmitted light image measuring camera for measuring transmitted light from the object, and a pixel within a contour of the transmitted light image of each measuring object. When the number of pixels indicating the amount of transmitted light falling within the preset range falls outside the preset pixel number range, the determination unit determines that the target object is a foreign object, and the determination unit determines A foreign matter removing device comprising: a separating unit that automatically separates a target object and a foreign matter based on a determination result. 3. A measuring light irradiating means for irradiating a measuring light to an object, a transmitted light image measuring camera for measuring a transmitted light from the object, and a pixel within a contour of the transmitted light image of each measuring object. When the difference between the amounts of transmitted light at any two pixels does not fall within a preset range, the object is determined to be a foreign object, and the object is determined based on the determination result of the determination unit. A foreign matter removing device comprising a separating means for automatically separating foreign matter from foreign matter. 4. A measuring light irradiating means for irradiating a measuring light to an object, a transmitted light image measuring camera for measuring a transmitted light from the object, and a pixel in an outline of the transmitted light image of each measuring object. When the number of times that the difference in the amount of transmitted light among a plurality of pixels falls within a preset range does not fall within the preset number range, the target object is determined to be a foreign substance. A foreign matter removing device comprising: means for automatically separating an object and a foreign matter based on a result of the determination by the determining means.