TWI803684B - Detection device - Google Patents

Abstract

The present invention provides a detection device that improves the detection accuracy of objects contained in a conveyed body. The detection device includes: a conveyance unit, a first light source, a first imaging unit, a first front window, a second light source, a second imaging unit, a second front window, a correction plate, and a detection unit. The transport unit transports and discharges the elongated object to be transported. The first light source irradiates light from above to the conveyed object being conveyed. The first imaging unit images the surface of the conveyed object. The first front window is arranged in front of the first imaging unit. The second light source irradiates light from below toward the discharged object to be conveyed. The second imaging unit is arranged under the conveying unit in plan view, and photographs the back surface of the object to be transported. The second front window is disposed below the conveyance unit and in front of the second imaging unit in plan view. The correction plate is arranged to face the second light source. The detection unit detects the target object based on the captured image of the object to be conveyed.

Description

Detection device

Embodiments of the present invention relate to a detection device.

Conventionally, there is known a detection device that uses light irradiated from a light source to image an object conveyed by a conveyance unit to detect objects such as foreign matter contained in the object.

In addition, there is an inspection device that has two imaging units, one imaging unit images the surface of the object from above, and the other imaging unit images the back surface of the object from below.

[Prior art literature] [Patent Document] [Patent Document 1] Japanese Patent No. 4308318

However, in the detection device, it is required to improve the detection accuracy of the object contained in the conveyed body.

In the case of the detection device that uses two imaging units to photograph the object as described above, the imaging unit for imaging the back of the object is placed below the object. However, the front window arranged in front of the imaging unit is contaminated by peeling objects from the conveyed object, and the imaging accuracy is reduced. As a result, the detection accuracy is reduced.

The problem to be solved by the present invention is to provide a detection device capable of improving the detection accuracy of an object contained in a conveyed body.

A detection device according to an embodiment includes a conveyance unit, a first light source, a first imaging unit, a first front window, a second light source, a second imaging unit, a second front window, a correction plate, and a detection unit. The conveyance unit conveys the elongated object to be conveyed in a predetermined conveyance direction, and releases the object to be conveyed from the conveyance end. The first light source irradiates light from above toward the object being conveyed by the conveying unit. The first imaging unit images the surface of the object to be conveyed with light irradiated from the first light source. The first front window is arranged in front of the first imaging unit to transmit light. The second light source irradiates light from below toward the object to be conveyed released from the conveyance end of the conveyance unit. The second imaging unit is disposed below the conveying unit in plan view, and images the back surface of the object to be transported with light irradiated from the second light source. The second front window is disposed in front of the second imaging unit below the conveyance unit in plan view, and transmits light therethrough. The correction plate is disposed so as to face the second light source, and corrects the received light amount. The detection unit extracts a color corresponding to the object from each of the captured images of the object captured by the first imaging unit and the second imaging unit, and extracts an image region including the extracted color to detect the object.

In the detection device, the transport unit transports the object to be transported such that the longitudinal direction becomes parallel to the transport direction, and transports the object at a transport speed of 10 m/min or more. In addition, in the detection device, the second front window is disposed on a side surface on a downstream side in the conveying direction. In addition, in the detection device, when the object to be conveyed is released from the conveying end and flies in the air, the rear surface is imaged. In addition, in the detection device, the color of the conveyance unit and the correction plate are the same.

According to the present invention, it is possible to improve the detection accuracy of objects included in the conveyed body.

The detection device of the embodiment described below includes a conveyance unit, a first light source, a first imaging unit, a first front window, a second light source, a second imaging unit, a second front window, a correction plate, and a detection unit. The conveyance unit conveys the elongated object to be conveyed in a predetermined conveyance direction, and releases the object to be conveyed from the conveyance end. The first light source irradiates light from above toward the object being conveyed by the conveying unit. The first imaging unit images the surface of the object to be conveyed with light irradiated from the first light source. The first front window is arranged in front of the first imaging unit to transmit light. The second light source irradiates light from below toward the object to be conveyed released from the conveyance end of the conveyance unit. The second imaging unit is disposed below the conveying unit in plan view, and images the back surface of the object to be transported with light irradiated from the second light source. The second front window is disposed in front of the second imaging unit below the conveyance unit in plan view, and transmits light therethrough. The correction plate is disposed so as to face the second light source, and corrects the received light amount. The detection unit extracts a color corresponding to the object from each of the captured images of the object captured by the first imaging unit and the second imaging unit, and extracts an image region including the extracted color to detect the object.

In addition, the conveying part of the detection device of the embodiment described below conveys the object to be conveyed so that the longitudinal direction becomes parallel to the conveying direction, and conveys at a conveying speed of 10 m/min or more.

(The overall structure of the detection device) FIG. 1 is a diagram showing the overall configuration of a detection device according to an embodiment. As shown in FIG. 1 , the detection device 1 has: a conveying unit 3, a first light source 11, a first imaging unit 21, a first front window 2a, a second light source 12, a second imaging unit 22, a second front window 4a, a correction board 121 , detection unit 30 (see FIG. 2 ), and power supply unit 40 (see FIG. 2 ).

The inspection device 1 irradiates light from the first light source 11 to the object W to be conveyed and moves in the conveyance direction D (the first conveyance direction D1 ), which is conveyed by the conveyance unit 3 arranged vertically below the detector 1 , and photographs it from above. The object F (object F1 ) such as a foreign object contained in the upper surface of the object W to be conveyed is detected by the first light source 11 irradiating the object W with light, or whether it is attached to the object F. Presence or absence of object F (object F1 ) such as foreign matter on the upper surface of W.

In addition, the detection device 1 irradiates light from the second light source 12 on the object W that is released from the conveying end 3 a of the conveying unit 3 and moves in the conveying direction D (second conveying direction D2 ), and photographs the object W from the second light source 12 from below. Two light sources 12 irradiate the object W with light, thereby detecting the presence or absence of objects F (objects F2 ) such as foreign matter contained in the lower surface of the object W that is to be the back surface, or whether objects F2 that have adhered to the object W are detected. Presence or absence of the object F (object F2 ) such as foreign matter on the lower surface of the back surface.

In addition, the detection device 1 has a first housing 2 . The first frame body 2 is disposed directly above the conveying unit 3 , and is, for example, in the shape of a rectangular box, accommodating the first light source 11 and the first imaging unit 21 . The first frame body 2 includes a material that blocks external light. For example, the first housing 2 can be configured as a sealed structure for preventing cleaning liquid such as water from entering the inside from the outside. In addition, the first frame body 2 may be properly partitioned by a partition plate to form a plurality of spaces inside the first frame body 2 .

In addition, in order to prevent the first light source 11 and the first imaging unit 21 from falling toward the conveyance unit 3 or to protect the first light source 11 and the first imaging unit 21, the first frame body 2 serves as the first light source 11 and the first imaging unit. A first front window 2a through which light is transmitted is disposed on the conveyance section 3 side of the front surface of the section 21 . The first front window 2a is a transparent resin panel.

In addition, the detection device 1 has a second housing 4 . The second frame body 4 is arranged directly under the conveyance unit 3 , and is, for example, in the shape of a rectangular box, and accommodates at least the second imaging unit 22 . Like the first frame body 2 , the second frame body 4 includes a material that blocks external light, and can be, for example, an airtight structure for preventing cleaning fluid such as water from entering the inside from the outside. In addition, the second housing 4 may be appropriately partitioned by a partition plate so that a plurality of spaces may be formed inside the second housing 4 .

In addition, in order to protect the second imaging unit 22, the second housing 4 is arranged so that the light is placed on the side surface of the second housing 4 that becomes the front side of the second imaging unit 22 and becomes the downstream side of the first conveying direction D1 of the conveying unit 3. Through the second front window 4a. The second front window 4 a is arranged in front of the second imaging unit 22 below the conveyance unit 3 in plan view.

Like the first front window 2a, the second front window 4a is a transparent resin panel. In addition, the second housing 4 accommodates, for example, a later-described image processing controller 31 constituting the detection unit 30 (see FIG. 2 ) in addition to the second imaging unit 22 .

The conveying unit 3 is, for example, a belt conveyor that hangs a belt between two rollers. When the conveyance part 3 is a belt conveyor, the conveyance surface of the conveyance part 3 is formed by the belt surface of the endless belt. Such a conveyance unit 3 conveys the object W to be conveyed in the first conveyance direction D1 (for example, the horizontal direction) along with the advancing direction of the belt. The belt constituting the loop of the conveyance unit 3 is, for example, white.

Moreover, the conveyance part 3 discharges the to-be-conveyed object W from the conveyance end part 3a which is the terminal part of the 1st conveyance direction D1. The conveyed object W discharged from the conveying end portion 3 a moves (falls) while drawing a parabola toward the front and downward of the conveying unit 3 in the second conveying direction D2 .

The first light source 11 is a visible light irradiation unit including a light emitting diode (Light Emitting Diode, LED), and uses the power supplied from the power supply unit 40 (refer to FIG. The conveyed object W and the object F1 moving in the first conveying direction D1 on the conveying surface 3 are irradiated with light in a wavelength band of, for example, 350 nm to 780 nm.

The first imaging unit 21 is, for example, a camera including an imaging element such as a charge coupled device (Charge Coupled Device, CCD) or a complementary metal oxide semiconductor (Complementary Metal Oxide Semiconductor, CMOS). The first imaging unit 21 images the object W to be transported using the light irradiated by the first light source 11 . The first imaging unit 21 captures reflected light of the light irradiated by the first light source 11 .

The number of pixels of the imaging element of the first imaging unit 21 is, for example, 5 million pixels. However, the number of pixels of the imaging element of the first imaging unit 21 may be appropriately changed in accordance with the size of the object to be conveyed W and the object F1 or the required detection accuracy. In addition, the first imaging unit 21 outputs the captured image of the conveyed object W to the detection unit 30 (see FIG. 2 ).

The second light source 12 is arranged in front of and below the conveying end portion 3 a of the conveying unit 3 . The second light source 12 is a visible light irradiation unit including an LED, and is released from the conveying end portion 3 a of the conveying unit 3 to move (fall) in the second conveying direction D2 by using electric power supplied from the power supply unit 40 (see FIG. 2 ). The conveyed body W and the object F2 are irradiated with light in a wavelength band of, for example, 350 nm to 780 nm in the same manner as the first light source 11 .

The second imaging unit 22 is arranged below the conveying unit 3 in plan view. The imaging lens of the second imaging unit 22 is directed forward and obliquely upward of the conveyance unit 3 .

Like the first imaging unit 21 , the second imaging unit 22 is, for example, a camera having imaging elements such as CCD or CMOS. The second imaging unit 22 images the object W to be conveyed using the light irradiated by the second light source 12 . The second imaging unit 22 captures reflected light of the light irradiated by the second light source 12 .

The number of pixels of the imaging element of the second imaging unit 22 is, for example, 5 million pixels. However, the number of pixels of the imaging element of the second imaging unit 22 may be appropriately changed in accordance with the size of the object to be conveyed W and the object F2 or the required detection accuracy.

The correction plate 121 is disposed in front of the conveyance unit 3 so as to face the second light source 12 . In addition, the correction plate 121 is arranged such that the plate surface faces the imaging lens of the second imaging unit 22 . The correction plate 121 is a white reflective plate that corrects the light reception amount of light from the second light source 12 and is preferably made of Teflon (registered trademark).

However, in this embodiment, the color of the conveying part 3 is white, specifically, the circulating tape is white, and the correction plate 121 is a white reflective plate, but the present invention is not limited thereto. The color of the conveying unit 3 and the color of the correcting plate 121 may be any color as long as the first imaging unit 21 and the second imaging unit 22 can capture and detect foreign matter that may be mixed into or attached to the object W. In addition, the color of the conveyance part 3 and the color of the correction plate 121 may be different.

The object to be conveyed W is, for example, foodstuffs, tablets, agricultural crops, and the like. The object W to be conveyed is elongated and has a shape in which the front, rear, and left and right sides in the conveyance direction D are curved. Therefore, by imaging both the front surface and the back surface of the object W, the front, rear, and left and right sides can be imaged. The object F is, for example, a foreign object that may be mixed into or attached to the object W during the manufacturing process of the object W.

In addition, in FIG. 1, the detection procedure in the case where the object W to be conveyed is "foodstuffs" is illustrated. In this case, the frozen or semi-frozen to-be-conveyed object W is conveyed from the front-stage conveyance part 5 on the upstream side of the conveyance part 3 , and is discharged from the discharge machine 6 toward the conveyance part 3 . The inner surface of the discharged object W is photographed while it is being conveyed by the conveyance unit 3 , and the rear surface is photographed while it is released from the conveyance end 3 a and flies in the air.

The object to be conveyed W that has been released from the conveyance end portion 3a lands in the storage portion 7, and is accommodated, for example, or conveyed toward a subsequent device.

The conveyance part 3 conveys the to-be-conveyed object W so that the longitudinal direction may become parallel with respect to the 1st conveyance direction D1. Thereby, rolling of the elongate to-be-conveyed object W in the 1st conveyance direction D1 can be suppressed.

In addition, the conveyance part 3 conveys the object W to be conveyed at a conveyance speed of 10 m/min or more. The conveying unit 3 preferably conveys the object W to be conveyed at 40 m/min. Accordingly, the conveyed object W can be released from the conveying end portion 3a at an appropriate flight distance, and the imaging time by the second imaging unit 22 can be secured and damage to the conveyed object W caused by landing can be reduced.

In addition, the conveyance part 3 is configured so that a plurality of to-be-conveyed objects W are aligned and conveyed in the first conveyance direction D1, whereby the plurality of to-be-conveyed objects W can be continuously moved toward the first light source 11 and the first imaging unit 21. move below.

The detection device 1 has: an output unit, which is used to output various information such as the operation status of the detection device 1; an input unit, which is used to input various instructions such as an operation instruction of the detection device 1; and a storage unit, which stores and corresponds to the color of the object F. Information related to the range of , or programs or parameters that control the operations of each part of the detection device 1 . The storage unit includes an internal storage device such as a random access memory (Random Access Memory, RAM), and an external storage device such as a hard disk drive (Hard Disk Drive, HDD) or a solid state disk (Solid State Disk, SSD).

As described above, the detection device 1 includes the detection unit 30 and the power supply unit 40 (both refer to FIG. 2 ). The detection unit 30 detects the presence or absence of the objects F1 and F2 contained in the object to be transported W, or whether the objects F2 are attached to the object W, based on the result of image processing of the input images from the first imaging unit 21 and the second imaging unit 22 . An image recognition processing device for the presence or absence of the object F1 and the object F2 of the conveyed body W.

The detection unit 30 extracts, for example, colors corresponding to the objects F1 and F2 from input images from the first imaging unit 21 and the second imaging unit 22, and extracts image regions having the extracted colors to detect the objects. F1, presence or absence of object F2. A further configuration of the detection unit 30 will be described later using FIG. 2 .

The power supply unit 40 supplies drive power to the first light source 11 , the first imaging unit 21 , the second light source 12 , the second imaging unit 22 , and the detection unit 30 . A further configuration of the power supply unit 40 will be described later using FIG. 2 .

In addition, the detection device 1 may include, for example, a blower as a cooling mechanism for a waterproof outdoor panel cooler on the outside of the first housing 2 and the second housing 4 . The air blower performs ventilation accompanying heat dissipation, dehumidification, and cooling of the insides of the first housing 2 and the second housing 4 .

(Control system of detection device) FIG. 2 is a diagram showing an example of a control system of the detection device according to the embodiment. As shown in FIG. 2 , in the control system of the detection device 1 , the detection unit 30 includes, for example, an image processing controller 31 and a programmable logic controller (Programmable Logic Controller, PLC) 32 .

The image processing controller 31 extracts, for example, images corresponding to the surface and The color of the object F1 and the object F2 (see FIG. 1 ) on the back surface is extracted, and the image area with the extracted color is extracted to detect the presence or absence of the object F1 and the object F2.

PLC32 is a control device, and it has, as mentioned above: an output unit for outputting various information such as the operation status of the detection device 1; an input unit for inputting various instructions such as operation instructions of the detection device 1; and a storage unit for storing and The information corresponding to the range of the color of the object F1 and the object F2 , or a program or parameter for controlling the operation of each part of the detection device 1 .

When the detection result (image recognition system signal S12 ) from the video processing controller 31 is input to the PLC 32 , it outputs a control signal S21 based on the detection result to, for example, a display operation unit 50 such as a touch panel. Moreover, PLC32 outputs each control signal S23 other than the input/output signal S22 to an external apparatus.

The power supply unit 40 includes, for example, a primary-side power supply 41 , a control power supply 42 , and a light source power supply 43 . The primary power supply 41 is a voltage supply source for the control power supply 42 and is connected to the control power supply 42 by wiring. The control power supply 42 is directed to each device to be controlled, that is, the first light source 11, the first imaging unit 21, the second light source 12, the second imaging unit 22, the detection unit 30 (image processing controller 31 and PLC 32), and the display operation The unit 50 supplies a voltage V1.

In addition, the control power supply 42 supplies respective voltages V2 to the first light source 11 and the second light source 12 via the light source power supply 43 .

As described above, the detection device 1 of the embodiment includes: the conveyance unit 3, the first light source 11, the first imaging unit 21, the first front window 2a, the second light source 12, the second imaging unit 22, the second front The window 4 a , the correction plate 121 , and the detection unit 30 . The conveyance unit 3 conveys the elongated object W to be conveyed in a predetermined conveyance direction D ( D1 ), and releases the object W to be conveyed from the conveyance end portion 3 a. The first light source 11 irradiates light from above to the object W being conveyed by the conveying unit 3 . The first imaging unit 21 images the surface of the object W to be transported using the light irradiated from the first light source 11 . The first front window 2 a is arranged in front of the first imaging unit 21 to transmit light therethrough. The second light source 12 irradiates light from below toward the object W to be conveyed, which is released from the conveyance end 3 a of the conveyance unit 3 . The second imaging unit 22 is arranged below the conveying unit 3 in plan view, and images the back surface of the object W to be transported using light irradiated from the second light source 12 . The second front window 4 a is arranged in front of the second imaging unit 22 below the conveyance unit 3 in plan view, and transmits light therethrough. The correction plate 121 is disposed so as to face the second light source 12, and corrects the received light amount. The detection unit 30 extracts the color corresponding to the object F ( F1 , F2 ) from each of the captured images of the conveyed object W captured by the first imaging unit 21 and the second imaging unit 22 , and extracts colors including the extracted colors. The image area to detect objects F1 and F2.

In the detection device 1 of the embodiment, since the object W is imaged from below, that is, the second imager 22 that images the back surface of the object W, and the second front window that protects the second imager 22 in front of the second imager 22 4a is not located directly below the conveyed object W released from the conveying end portion 3a of the conveying unit 3, and therefore, for example, debris that has been peeled off from the conveyed object W does not adhere to the second front window 4a. Therefore, contamination of the second front window 4 a can be suppressed, thereby suppressing a decrease in imaging accuracy by the second imaging unit 22 , and as a result, the detection accuracy of the object F ( F2 ) included in the conveyed body W can be improved. .

In addition, the second imaging unit 22 photographs the object to be conveyed W that has been released from the conveyance unit 3 from obliquely below the rear in the second conveyance direction D2. The object W to be transported is photographed at the position. Thereby, imaging can be performed over the entire back surface of the object to be conveyed W, and thus the detection accuracy of the object F2 contained in the object to be conveyed W can also be improved.

In addition, the conveying unit 3 of the detecting device 1 according to the embodiment conveys the object W to be conveyed so that the longitudinal direction becomes parallel to the conveying direction D ( D1 ), and conveys the object W at a conveying speed of 10 m/min or more.

By conveying the object W so that its longitudinal direction becomes parallel to the conveying direction D (first conveying direction D1), even if the object W is elongated, it does not move in the conveying direction D (first conveying direction D1) during conveyance. - Since the transport direction D1) rolls, the transport of the object W to be transported by the transport unit 3 is stabilized. In addition, by conveying the object W at a conveying speed of 10 m/min or more, the object W can be released from the conveying end 3 a at an appropriate flying distance, and the imaging time by the second imaging unit 22 can be secured.

In addition, in the above-described embodiment, the detection of the object F (F1, F2) by the detection unit 30 is detection based on color extraction of visible light, but is not limited thereto, and may be applied to, for example, ultraviolet light or infrared light. A device for detection to detect objects F (F1, F2).

Although the present invention has been disclosed above with the embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field may make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention should be defined by the scope of the appended patent application.

1: Detection device 2: The first frame 2a: First front window 3:Transportation department 3a: Transfer end 4: The second frame 4a: Second front window 5: Front section conveying department 6: discharge machine 7: Containment 11: The first light source 12: Second light source 21: The first filming department 22: The second filming department 30: Detection Department 31: Image processing controller 32:PLC 40: Power supply unit 41: Primary side power supply 42: Control power supply 43: Light source power supply 50: display operation part 121: Correction plate D: Transport direction D1: The first conveying direction D2: Second conveying direction F, F1, F2: object S11a, S11b, S12: Image recognition system signal S21, S23: control signal S22: Input/Output Signal V1, V2: Voltage W: Object to be transported

FIG. 1 is a diagram showing the overall configuration of a detection device according to an embodiment. FIG. 2 is a diagram showing an example of a control system of the detection device according to the embodiment.

1: Detection device

2: The first frame

2a: First front window

3:Transportation department

3a: Transfer end

4: The second frame

4a: Second front window

5: Front section conveying department

6: discharge machine

7: Containment

11: The first light source

12: Second light source

21: The first filming department

22: The second filming department

31: Image processing controller

121: Correction plate

D: Transport direction

D1: The first conveying direction

D2: Second conveying direction

F, F1, F2: object

W: Object to be transported

Claims (5)

A detection device, comprising: a conveying section conveys the elongated object to be conveyed in a predetermined conveying direction, and releases the object to be conveyed from the conveying end; a first light source that irradiates light from above toward the object being conveyed by the conveying unit; a first imaging unit for imaging the surface of the object to be transported with light irradiated from the first light source; a first front window, arranged in front of the first photographing unit, to allow light to pass through; a second light source that irradiates light from below toward the object to be conveyed released from the conveyance end of the conveyance unit; a second imaging unit arranged below the conveying unit in a plan view, and photographs the back surface of the object to be transported with light irradiated from the second light source; The second front window is disposed in front of the second imaging unit below the conveying unit in plan view, and allows light to pass through; a correction plate arranged in such a manner as to face the second light source, and to correct the received light amount; and The detection unit extracts a color corresponding to the object from each of the captured images of the conveyed object captured by the first imaging unit and the second imaging unit, and extracts an image including the extracted color. area to detect the object. The detection device according to claim 1, wherein the conveying part conveys the object to be conveyed in such a way that the longitudinal direction is parallel to the conveying direction, and the conveying speed is 10 m/min or more. transport. The detection device according to claim 1, wherein the second front window is arranged on a side surface on the downstream side in the conveying direction. The detection device according to claim 1, wherein when the conveyed object is released from the conveying end and flies in the air, the back surface is photographed. The detection device according to claim 1, wherein the color of the conveying part and the correction plate are the same.

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