JPH07121386B2 - Foreign matter removal device - Google Patents

Description

Detailed Description of the Invention

[0001]

The present invention relates to a number of the transparent body, for example, glass pieces in such recovered cullet relates foreign matter removing device you separate and remove opaque foreign matter such as ceramics and stone or metal.

[0002]

2. Description of the Related Art The applicant of the present invention has already proposed such a device as disclosed in Japanese Patent Laid-Open No. 3-75545. In this conventional apparatus, an object in which an opaque foreign substance is mixed in a transparent body is conveyed by a belt conveyor, and a linearly polarized laser beam is horizontally scanned while being dispersed and discharged from the conveyance end of the belt conveyor. The reflected light from the object is received by the CCD of the CCD camera (solid-state image sensor camera) via the polarization filter, and the pixel output of the CCD camera (output of each CCD) is digitally image processed to make the object transparent. Determine whether it is a body or an opaque foreign substance.

That is, in the case of a transparent body, most of the laser beam is transmitted and only a small part thereof is reflected, but the reflected light remains linearly polarized light and is cut by the polarizing filter. On the other hand, in the case of opaque foreign matter,
Diffuse reflection causes circular polarization, and most of the light passes through the polarization filter and enters the CCD. Therefore, the output of the CCD is very small for the transparent body and large for the opaque foreign matter, and the difference between the transparent body and the opaque foreign matter can be discriminated. Therefore, in the case of opaque foreign matter, air is blown during the fall from the conveyor to separate it from the transparent body.

[0004]

By the way, in the recovery cullet, in addition to non-metallic foreign substances such as ceramics and stones, aluminum caps used for bottles, etc. Aluminum seal pieces used,
It often contains non-ferrous metal foreign substances such as various aluminum fragments. Even if such a non-ferrous metal foreign substance is opaque, its shape is largely different from that of non-metallic foreign substances such as ceramics and stones, and the reflection mode of light is also different. In the above-mentioned conventional apparatus, which is the main focus, there are many things that cannot be classified as foreign matter.

Therefore, the non-ferrous metal (non-magnetic metal) such as the aluminum cap, the aluminum seal piece, and the aluminum piece as described above.
It is conceivable to apply a non-magnetic metal separating device, which has been widely used in the related art, to the conveyance end portion of the belt conveyor in order to separately remove the foreign matter. That is, as shown in FIG. 14, a magnet rotor 4 having a plurality of permanent magnets 3 is incorporated in a pulley 2 at the end of conveyance of a belt conveyor 1, and an induced current is generated in a non-ferrous metal foreign matter 5 by rotating the magnet rotor 4 at high speed. Then, when the non-ferrous metal foreign matter 5 falls from the belt conveyor 1, the non-ferrous metal foreign matter 5 is blown farther than the other target 6 by the magnetic repulsive force with the magnetic field of the permanent magnet 3 to be separated.

However, in this case, the ability to separate non-metallic foreign substances such as ceramics and stones is significantly reduced. That is, in the first place, the foreign matter separating device irradiates the object falling from the conveyance end of the belt conveyor 1 with the laser beam 8 from the laser light scanning device 7 in order to remove the opaque foreign matter from the transparent body such as the recovery cullet. Since the CCD camera 9 receives the reflected light from the object to determine whether it is a transparent body or an opaque foreign material, the non-ferrous metal foreign material 5
Is separated from other objects 6 as described above, and the belt conveyor 1
When it is dropped so as to fly away from the laser beam, the laser beam 8 is blocked by the non-ferrous metal foreign matter 5, and the transparent body and non-metallic foreign matter such as ceramics and stones are not irradiated. Further, even if the non-ferrous metal foreign substance 5 is dropped separately from the other target 6, if it is discriminated as an opaque foreign substance by reflecting the laser beam 8, it is confused by the separation because it is jetted with air. Will cause

An object of the present invention is to remove foreign substances of non-ferrous metal (non-magnetic metal) such as aluminum caps, aluminum seal pieces and aluminum fragments without impairing the function of separating non-metallic foreign substances such as ceramics and stones. It is to completely separate and remove such non-metallic foreign matter.

[0008]

DISCLOSURE OF THE INVENTION The present invention is a foreign matter removing apparatus for removing foreign matters of non-ferrous metal which are mixed while transporting a large number of transparent bodies and the like by a conveyor, and which is provided in the middle of a convey path by the conveyor. , A magnetic generation means for forming a magnetic field to levitate the non-ferrous metal foreign matter from the conveyor by a magnetic repulsive force due to an induced current, and a vacuum means for sucking and removing the levitated non-ferrous metal foreign matter. .

Further, as described above, an object in which opaque foreign substances are mixed in a transparent body is conveyed by a conveyor, and while being dispersed and discharged from the conveyor, the laser beam from the laser beam scanning device makes a horizontal straight line. The solid-state image sensor camera receives the reflected light from the object, and the pixel output from the solid-state image sensor camera is digitally processed by the image processing circuit to determine whether it is a transparent body or an opaque foreign substance. Then
In the case of a foreign substance removing device in a transparent body that ejects air from a nozzle when it is an opaque foreign substance, a magnetic field is formed in the middle of the convey path by the conveyor to generate a magnetic repulsion force of the non-ferrous metal foreign substance by the induced current. There is provided a magnetism generating means for levitating from the conveyor and a vacuum means for sucking and removing the levitated non-ferrous metal foreign matter.

The magnetism generating means is preferably a rotating magnet rotor having a plurality of magnetic poles arranged in the circumferential direction, but may be an electromagnetic coil.

[0011]

When a non-ferrous metal foreign substance enters the magnetic field formed on the way of the conveying path by the magnetic generation means, a current is induced in the non-ferrous metal foreign substance to generate a magnetic repulsive force with the magnetic field.
Non-ferrous metal foreign material floats from the conveyor. The floating non-ferrous metal foreign matter is immediately sucked by the vacuum means and removed from the conveyor. Further, the suction action of the vacuum means also removes paper, plastic film, dust and the like.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an overall schematic configuration of a foreign matter removing apparatus according to the present invention. This removing device includes a hopper 21, a dispersion feeder 22, a vibrator 23, and a white belt conveyor 14
And an object 15 conveyed on the belt conveyor 14.
The non-ferrous metal foreign matter removing magnet rotor 32 and the vacuum duct 33 for sucking and removing the non-ferrous metal (non-magnetic metal) foreign matter from inside, and the black foreign matter (stone etc.) that does not reflect light from the object 15 are detected. Black foreign matter detection diffused light source 24, black foreign matter detection CCD camera 25, and black foreign matter detection image processing device (including computer) 26
And an opaque foreign object detecting laser light scanning device 10 for detecting an opaque foreign object (ceramic etc.) that reflects light from the object 15, an opaque foreign object detecting CCD camera 12, and an opaque foreign object detecting image processing device (computer 27)
And an air ejecting device 28 for blowing off a foreign substance, and a foreign substance elimination control circuit for operating the air ejecting device 28 when any one of the black foreign substance detecting image processing device 26 and the opaque foreign substance detecting image processing device 27 detects a foreign substance. 29
And a collection container 30 having a transparent body collection unit 19 and a foreign matter collection unit 20.

A large number of objects 15 in which foreign substances are mixed in a transparent body such as a recovery cullet are thrown into the hopper 21,
It is conveyed while being dispersed on the dispersion feeder 22 vibrated by the vibrator 23, transferred on the belt conveyor 14, and passes above the magnet rotor 32. The magnet rotor 32 has a plurality of permanent magnets 34 having N poles and S poles alternately arranged in the circumferential direction.
It is rotated at a high speed between the upper part 14A that moves forward and the lower part 14B that moves backward, and an alternating magnetic field is formed during the conveyance of the belt conveyor 14. The vacuum duct 33 is provided above the belt conveyor 14, and the suction port at the lower end thereof is
It is located slightly above the upper portion 14A of the belt conveyor 14.

Therefore, when a non-ferrous metal foreign substance such as an aluminum cap, an aluminum seal piece, or an aluminum shard is mixed in the object 15, when the non-ferrous metal foreign substance enters the alternating magnetic field by the magnet rotor 32, an eddy current is generated in the non-ferrous metal foreign substance itself. Is induced and the magnetic repulsive force with the alternating magnetic field causes the belt conveyor 1
Elevated from 4. Then, the floating non-ferrous metal foreign matter is immediately sucked into the vacuum duct 33 and removed from the belt conveyor 14, and the vacuum duct 33 is removed.
To a collection container (not shown). At this time, paper, plastic film, dust, etc. are also sucked into the vacuum duct 33 and removed from the belt conveyor 14. Alternatively, an electromagnetic coil may be used, and a high frequency current may be applied to generate an alternating magnetic field.

The object 15 from which the non-ferrous metal foreign matter is removed is
The image is taken from above by the CCD camera 25 while being further conveyed on the belt conveyor 14 and being irradiated with diffused light from the diffused light source 24. At this time, black foreign matter is detected on the belt conveyor 1.
Since 5 is white, it is detected by the black foreign matter detection image processing 26.

Further, the object 15 is the belt conveyor 14
The laser beam 16 from the laser beam scanning device 10 scans in a horizontal straight line during the fall, and the reflected light is a CCD image of a CCD camera 12 equipped with a polarization filter. It is detected by the sensor 31.

Laser beam scanning device 10 and CCD camera 12
Means the former laser light projection optical axis 11 and the latter light receiving optical axis 1
3 are installed so as to be located on the same plane, and these scan an object 15 falling from the belt conveyor 14 from an obliquely upper side with a laser beam 16 from the laser beam scanning device 10 at an angle (for example, 45 degrees). The reflected light from the object 15 is received through the polarization filter by the CCD camera 12 having the same angle as the directivity angle.

Since the laser beam projection optical axis 11 of the laser beam scanning device 10 and the light receiving optical axis 13 of the CCD camera 12 are located on the same plane (same height), as shown in FIG. The light receiving optical axis 13 intersects the laser light projecting optical axis 11 at a point a on the parabolic locus A, and intersects the laser light projecting optical axis 11 at a point b on the parabolic trajectory B. Therefore, the object falling along the parabola locus A is irradiated with the laser beam 16 from the upper oblique front at the point a, and the reflected light enters the CCD camera 12, and the parabola locus B is also reflected.
The object falling along the path is the laser beam 1 at the point b.
6 is irradiated and the reflected light thereof similarly enters the CCD camera 12.

The output from the image sensor 31 of the CCD camera 12 is analyzed by the image processing device 27 to determine whether it is a transparent body or an opaque foreign matter,
The air injection device 28 is controlled according to the determination result. Here, in the case of the transparent body 15a, it drops into the transparent body collecting portion 19 of the collection container 30 as it is, whereas in the case of the opaque foreign material 15b, air is jetted from the air jetting device 28. It falls into the foreign matter collection unit 15b. Similarly, the black foreign matter detected by the black foreign matter detection image processing 26 is dropped into the foreign matter collecting unit 15b by the air jetting device 28 jetting air.

As shown in FIGS. 3 and 4, the air injection device 28 has, for example, 20 nozzles 38 arranged in a horizontal row, and the same number of nozzles 38 arranged in a horizontal row in a one-to-one correspondence with the nozzles 38. The solenoid valve 39 and one receiver tank 40 common to these solenoid valves 39 are arranged on a base 41. The entire air injection device 28 is shown in FIG.
As shown in FIG. 4, the air is obliquely installed on the pedestal 42 so that air can be jetted obliquely from above toward the opaque foreign matter 15b and the black foreign matter falling from the belt conveyor 14.

The structure of the nozzle 38 is shown in FIGS.
All nozzles 38 have two horizontally long plates 43.4 that are long in the left and right.
4 are overlapped with each other, and are formed at a constant interval on the left and right sides between the upper and lower horizontal plates 43 and 44. That is, on the lower surface of the upper horizontal plate 43, a large number of shallow recesses 45 are formed which gradually become thinner toward the front end face of the horizontal plate 43 in the vertical direction and gradually become wider in the horizontal direction. The lower horizontal plate 44 does not have such a recess, and the upper and lower horizontal plates 43, 44 are overlapped to close the lower surface of the entire recess 45 with the lower horizontal plate 44, so that the front end of the recess 45 is held. A nozzle 38 serving as an elongated ejection port 46 is formed. Further, each of the nozzles 3 is attached to the lower oblong plate 44.
A connection screw hole 47 is formed at the rear end of the connection hole 8. Each nozzle 38 is connected to a corresponding solenoid valve 39 via a pipe joint 48 screwed into the screw hole 47 and a pipe 49.

The receiver tank 40 is connected to a compressor (not shown). The compressed air stored in the receiver tank 40 is connected to 20 solenoid valves 39 through a pipe.
When a certain solenoid valve 39 is opened simultaneously, air is jetted from the slender jet port 46 of the nozzle 38 corresponding thereto. In this case, the inside of the nozzle 38 is gradually thinned in the vertical direction and gradually widened in the horizontal direction toward the injection port 46 at the tip thereof (the cross-sectional area is also gradually reduced toward the tip. However, the air is rectified because the inner portion of the nozzle 38 (in the vicinity of the connection screw hole 47) serves as a temporary air reservoir. Moreover, the air is squeezed in the vertical direction to determine the jetting direction and is spread in the lateral direction, so that it becomes a thin laminar flow spreading from the jet port 46 in the lateral direction, and reaches the place where the object 15 falls. By this time, the air from the adjacent nozzle 38 overlaps. It should be noted that the inner surface of the nozzle 38 may be provided with a ridge or the like that has a rectifying function.

FIG. 9 shows an electrical schematic configuration of the foreign matter removing apparatus of this example. The laser light scanning device 10 includes a laser light source 5
0, a rotary deflector 51, and a synchronization detector 52 are provided.
The laser beam from the laser light source 50 is reflected by the reflecting mirror 53 in FIG. 10 and further reflected by the rotating polygon mirror 54 of the rotary deflector 51 to become a laser beam 16 for scanning in a horizontal straight line. The image is projected repeatedly while monitoring the projection direction of the rotary deflector 51. The laser beam 16 is detected by the synchronization detector 52, and the synchronization detector 52 outputs a synchronization signal for each scanning.

Image sensor 31 of CCD camera 12
Is a so-called one-dimensional image sensor in which, for example, 1024 CCDs are arranged in a horizontal row, and the output from each CCD is 1 by the camera controller 55 in accordance with the synchronization signal from the synchronization detector 52 of the laser beam scanning device 10. It is taken out for each scan, converted into a binary electric signal by a binarization circuit 56 with a constant threshold value as a reference, then taken into a computer 57, and stored in a memory in the computer 57. The voltage output from each CCD is the laser beam 16
The object 15 scanned by is different depending on whether it is a transparent body or an opaque foreign material. That is, the reflected light from the opaque foreign material 15b is mainly circularly polarized light and passes through the polarizing filter, whereas the reflected light from the transparent body 15a is a small amount and most of it is linearly polarized light and is blocked by the polarizing filter. Therefore, the output voltage from each CCD is transparent when the opaque foreign material 15b is transparent.
Much higher than in.

Such a difference can be further improved if the same transparent body and the same opaque foreign substance are subjected to scanning by the laser beam scanning device 10 a plurality of times and AND logic is applied to the output of the image sensor 31 for the number of scanning times. growing. Therefore, in this example, every time the laser beam scanning device 10 performs two scans, the two outputs from the image sensor 31 are binarized and ANDed.

In the case of this example, the CCD of the image sensor 31
Is 1024, whereas the number of nozzles 38 of the air jetting device 28 is 20, which is far smaller than the number of CCDs. Therefore, in this example, CC is set for one nozzle.
For example, 1024 CCDs are divided into 20 blocks by associating 51 Ds with each other, and transparent / opaque discrimination is made for each block by the 51 CCDs. In this case, since 51 × 20 = 1020, four of the 1024 CCDs are left over, but the output is handled for the two CCDs at both ends of the CCDs arranged in a horizontal row. Excluding these without 10
The output of 20 CCDs is valid.

When it is determined that a certain CCD block is an opaque foreign substance, not only is one nozzle 38 corresponding to that CCD block ejected air, but also two nozzles on both sides adjacent to this nozzle 38. The solenoid valve 39 is controlled by the valve controller 58 so that the air is also jetted from the nozzle 38 of the same (the air from the adjacent nozzle 38 overlaps as described above). In the case of the black foreign matter detection by the black foreign matter detection image processing device 26, the air jet is similarly performed.

In order to process the laser beam 16 that has not hit the falling object 15, the rear wall of the foreign matter collecting unit 20 is a backboard 17 made of a reflecting plate (for example, a stainless plate) as shown in FIG. . This backboard 1
The laser beam reflected from the front surface (mirror surface) of 7 is directed obliquely downward and does not enter the CCD camera 12. If foreign matter or the like that has been air-jetted adheres to the backboard 17 and is contaminated, the reflected light caused by the foreign matter may cause an erroneous detection when entering the CCD camera 12. A partition wall 20 that is slanted below the optical path of 16
a is provided, and the partition wall 20a and the oblique upper wall 20b of the foreign matter collecting unit 20 are provided with the partition wall 20a and the upper wall 20b.
A shielding wall 20c for preventing foreign matter from entering the space between and is provided, and the foreign matter sprayed with air as described above falls below the partition wall 20a.

FIG. 10 shows the scanning of the transparent body 15a and the opaque foreign material 15b by the laser beam from the laser beam scanning device 10, and the CCD of the image sensor 31 in the first scanning.
An analog signal that continuously represents the output of the group, an analog signal that similarly continuously represents the output of the CCD group of the image sensor 31 in the second scan, and an analog signal after binarizing these.
An AND signal for the same scan line subjected to D processing, a CCD block divided into 20 pieces as described above, a transparent / opaque discrimination result, the presence / absence of operation of 20 solenoid valves 39, and 20 nozzles. 38 shows the relationship with the presence or absence of air injection from 38. Further, in FIG. 12, analog signals from the CCD group of the image sensor 31 in the first scan and the second scan, and a binarization circuit 56 for these analog signals.
Binary signal binarized by and the AN after binarization
An AND signal for the same scan line subjected to D processing is shown.

FIG. 13 shows the flow of the discrimination operation of the transparent body or the opaque foreign matter and the sorting operation performed in the computer 57. First, in the initial setting of step 101, the number of CCDs per divided CCD block, that is, the CC to be made to correspond to each nozzle 38
The unit number N of D (51 in the above example) and the reference width T used as a reference for determining opacity / transparency are set depending on the width of the AND signal.

Thereafter, at step 102, the binarization circuit 56
Capture the binary signal of the first scan from and store it in the memory,
Subsequently, similarly, in step 103, the binary signal of the second scan is captured and stored in the memory, and then these are processed in step 104.
AND processing in. Next, for the same scan line, in step 105, the rising address and falling address of each AND signal are detected. That is, for each AND signal, the rising edge and the falling edge are C arranged in a horizontal row.
It is detected which position in the CD group corresponds to the CCD and C
The position of the CD according to the array order is stored in memory for each AND signal.

At the next step 106, it is sequentially determined from the AND signal on the left, which AND signal from each block of the divided CCD blocks corresponds to which nozzle 38. It is calculated one by one by the following calculation. That is, the first AND
If the rising address of the signal is D1 as shown in FIG. 17, the rank X of the nozzle 38 corresponding to this AND signal is
From D1 and the number of units N, X = (D1 / N) +1. However, X is a positive integer. For example, when N is set to "51" as described above using FIG. 10 as an example, D1 becomes "4".
In the case of “20”, X becomes “9”, which corresponds to the ninth nozzle 38.

Then, in step 107, the width W between the rising edge and the falling edge of the AND signal is obtained by the number of CCDs between the rising address and the falling address. That is, in FIG. 10, the rising address of the first AND signal is D1 and the falling address is L as shown above.
If it is 1, the width W of this AND signal is W = (L1-D
It becomes 1).

Next, at step 108, it is judged if the width W of the AND signal exceeds the reference width T. If it exceeds, it proceeds to step 109 and it is judged that it is an opaque foreign substance. Go to and determine that it is a transparent body. For example, if (L1-D1)> T as in the first AND signal in FIG.
2) If <T, it is a transparent body. Then, in the case of opaque foreign matter, the process proceeds to step 111, and the three solenoid valves 39 are simultaneously operated under the control of the valve controller 58. That is, the above Xth, (X-1) th and (X +
1) The three solenoid valves 39 respectively corresponding to the three nozzles 38 are opened, air is simultaneously jetted from these three nozzles 38 and jetted onto the opaque foreign material 15b, and the opaque foreign material 15b is shown in FIG. It is dropped into the foreign matter collecting unit 20. In the example of FIG. 10, since it is determined that the ninth CCD block is an opaque foreign substance, the ninth nozzle 3
8 as well as 8th and 1st adjacent to both sides
Air is also jetted from the 0th nozzle 38.

In the next step 112, it is judged whether or not there is another AND signal for the same scan line, and if there is another AND signal, in step 113 the rising address and falling address of the next AND signal are read from the memory, and then the step Repeat the process from 106 to step 112,
When it is the opaque foreign material 15b, air is jetted in the same manner as above.

If there is no other AND signal for the same scan line, it is judged in step 114 whether or not there is a laser scanning stop command. If there is no stop command, step 10
Returning to step 2, the same process is repeated for the next scan, and if there is a stop command, the process ends.

If the output of the image sensor 31 is binarized and then AND processing is performed for three or more scans, the accuracy of discrimination between the transparent body and the opaque foreign matter can be further improved. The image sensor 31 is a CCD
The present invention is not limited to a so-called one-dimensional image sensor in which solid-state image pickup devices such as the above are arranged in a horizontal row, and may be a two-dimensional image sensor in which solid-state image pickup devices are arranged in a matrix.

Further, in the above example, the X-th one nozzle corresponding to the CCD block in which the opaque foreign matter is detected and the (X-1) -th and (X +)-th nozzles adjacent to the left and right sides of the nozzle.
Although the air is jetted simultaneously from the 1) th three nozzles, the nozzle width of each nozzle may be reduced to further jet air from the (X-2) th and (X + 2) th nozzles at the same time. , The number of nozzles for air ejection can be arbitrarily selected by changing the number of nozzles for air ejection according to the width of the AND signal.

[0039]

According to the present invention, the non-ferrous metal foreign matter is levitated by the magnetic repulsive force in the middle of the convey path of the conveyor, and the floating non-ferrous metal foreign matter is immediately sucked by the vacuum means. Non-ferrous metal (non-magnetic metal) foreign substances such as aluminum fragments can be completely separated and removed from such non-metallic foreign substances without impairing the function of separating non-metallic foreign substances such as ceramics and stones. Moreover,
It can be done on the same transport line, which is economical.
Further, the suction action of the vacuum means can remove paper, plastic film, dust and the like.

[Brief description of drawings]

FIG. 1 is a schematic view of an entire foreign matter removing device according to the present invention.

FIG. 2 is an explanatory diagram showing a relationship between a falling trajectory of an object falling from a belt conveyor, a laser beam from a laser beam scanning device, and an optical axis of a CCD camera in the foreign matter removing apparatus.

FIG. 3 is a plan view of the belt conveyor and an air injection device.

FIG. 4 is a perspective view of an air injection device.

FIG. 5 is a partially cutaway perspective view of a nozzle of the air injection device.

FIG. 6 is a horizontal sectional view of the same.

FIG. 7 is a vertical sectional view of the same.

FIG. 8 is a front view of the same.

FIG. 9 is a block diagram of an electrical schematic configuration of an opaque foreign matter sorting apparatus according to the present invention.

FIG. 10 is a schematic diagram illustrating processing from scanning with a laser beam to classification by air jetting in the same apparatus.

FIG. 11 is a partial cross-sectional view of a foreign matter collecting unit.

FIG. 12 is a timing chart showing a process of processing an output from the image sensor.

FIG. 13 is a flowchart showing a flow of processing in a computer.

FIG. 14 is a schematic configuration diagram of a reference example in which a non-ferrous metal foreign matter is removed at the conveyance end of a belt conveyor.

[Explanation of symbols]

 10 Laser Light Scanning Device 12 CCD Camera 14 Belt Conveyor 15a Transparent Body 15b Opaque Foreign Material 16 Laser Beam 32 Magnet Rotor 33 Vacuum Duct

Claims (4)

[Claims] 1. A foreign matter removing device for removing mixed foreign matters of non-ferrous metal while transporting a large number of transparent bodies and the like by a conveyor, wherein a magnetic field is formed in the middle of a convey path by the conveyer. A foreign matter removing device comprising: a magnetism generating means for floating foreign matter from a conveyor by a magnetic repulsive force due to an induced current; and a vacuum means for sucking and removing the floating non-ferrous metal foreign matter. 2. An object in which opaque foreign substances are mixed in a transparent body is conveyed by a conveyor, and while being dispersed, discharged and dropped from the conveyor, a laser beam from a laser beam scanning device scans the object in a horizontal straight line. Light reflected from an object is received by a solid-state image sensor camera, and pixel output from this solid-state image sensor camera is subjected to digital image processing by an image processing circuit to determine whether it is a transparent body or an opaque foreign matter, and When the foreign matter removing device in the transparent body that ejects air from the nozzle at the time, in the middle of the convey path by the conveyor, a magnetic field is formed to float the foreign matter of the non-ferrous metal from the conveyor by the magnetic repulsive force by the induced current A foreign matter removing device comprising: a generating means and a vacuum means for sucking and removing the floating non-ferrous metal foreign matter. 3. The magnetizing means is a rotating magnet rotor having a plurality of magnetic poles arranged in the circumferential direction.
Alternatively, the foreign matter removing device according to item 2. Wherein said magnetism generating means, foreign matter removing apparatus according to claim 1 or 2 which is an electromagnetic coil.