WO2022080373A1

WO2022080373A1 - Optical sorting machine

Info

Publication number: WO2022080373A1
Application number: PCT/JP2021/037754
Authority: WO
Inventors: 雅明定丸; 知幸宮本
Original assignee: 株式会社サタケ
Priority date: 2020-10-15
Filing date: 2021-10-12
Publication date: 2022-04-21
Also published as: JP7521570B2; GB202304656D0; JP2023017898A; GB2614190A; JP7188638B2; CN116368373A; JPWO2022080373A1

Abstract

This optical sorting machine comprises: a light source configured to irradiate, with light, a to-be-sorted object being transferred on a transfer path; an optical sensor configured to detect the light irradiated from the light source and associated with the to-be-sorted object; a determination unit configured to determine foreign matter and/or defective products for the to-be-sorted object on the basis of a signal obtained by the optical sensor with respect to the light associated with the to-be-sorted object; and an intermediate member that is placed at a position between the light source and the transfer path in a light irradiation direction from the light source to the to-be-sorted object, and at a position in which the detection of the light associated with the to-be-sorted object is not affected, the intermediate member having a marking. The optical sensor is further configured to detect a marking-related light irradiated from the light source and obtained through the marking.

Description

Optical sorter

This disclosure relates to an optical sorter.

An optical sorter that uses optical information obtained by an optical sensor when the object to be sorted is irradiated with light from a light source to identify and remove foreign substances and defective products contained in the object to be sorted has been conventionally known. (For example, Japanese Patent Application Laid-Open No. 61-212734). The optical information (for example, the color gradation value) obtained by the optical sensor is compared with the threshold value, and based on the comparison result, it is determined whether the object to be sorted is a good product, a foreign substance, or a defective product. To. The object to be sorted, which is determined to be a foreign substance or a defective product, is typically blown off by air injection, whereby the object to be sorted is sorted into a non-defective product, a foreign substance and a defective product.

However, the conventional optical sorter leaves room for improvement in order to improve the sorting accuracy.

This disclosure has been made to solve the above-mentioned problems, and can be realized, for example, in the following form.

According to the first aspect of the present disclosure, an optical sorter is provided. This optical sorter is configured to detect a light source configured to illuminate the object being transferred on the transfer path and light emitted from the light source and associated with the object to be sorted. An optical sensor, a determination unit configured to determine foreign matter and / or defective products for the object to be sorted, and a light source based on the signal acquired by the optical sensor with respect to the light associated with the object to be sorted. An intermediate member, which is located between the light source and the transfer path in the direction of irradiation of light from the object to be sorted and does not affect the detection of light associated with the object to be sorted, and has markings. I have. The optical sensor is further configured to detect marking-related light emitted from a light source and obtained through marking.

The "light associated with the object to be sorted" may be reflected light which is light reflected by the object to be sorted, may be transmitted light which is light transmitted through the object to be sorted, or may be. , Both reflected light and transmitted light may be used.

According to this optical sorter, it is possible to carry out various processes for improving the sorting accuracy based on the marking-related light detected by the optical sensor. For example, the amount of light from the light source can be detected based on the marking-related light, and it can be determined whether or not the amount of light is within an appropriate range. Further, since the intermediate member is arranged at a position where the optical sensor does not affect the detection of the light associated with the object to be sorted, the marking-related light can be detected during the sorting operation of the optical sorter. Moreover, since the optical sensor can be shared for the detection of the light associated with the object to be sorted and the detection of the marking-related light, it is not necessary to provide an additional optical sensor only for the detection of the marking-related light.

According to the second aspect of the present disclosure, in the first aspect, the optical sorter comprises a detector configured to detect the state of the optical sensor based on the detection result of the marking-related light. .. According to this embodiment, various processes for suppressing deterioration of sorting accuracy due to the state of the optical sensor can be performed based on the detected state of the optical sensor. For example, by notifying an abnormality regarding the state of the optical sensor, it is possible to suppress the operation of the optical sorter in a state where the sorting accuracy is deteriorated due to the state of the optical sensor. Alternatively, when the deterioration of the sorting accuracy is grasped, the detected state of the optical sensor can be used as information for clarifying the cause of the deterioration. The detected state of the optical sensor may include, for example, a state related to the installation position of the optical sensor.

According to the third aspect of the present disclosure, in the second embodiment, the state of the optical sensor detected by the detection unit is the presence / absence of misalignment of the optical sensor, the amount of misalignment, the direction of misalignment, and the optics. Includes at least one of the presence or absence of out-of-focus of the sensor. According to this embodiment, various processes for suppressing deterioration of sorting accuracy due to positional deviation or focus deviation of the optical sensor can be performed.

When the state of the optical sensor detected by the detection unit includes the amount and direction of misalignment, it is easy to carry out processing or measures to prevent deterioration of sorting accuracy due to misalignment. For example, the user can easily grasp in which direction and by what distance the installation position of the optical sensor should be moved when performing the adjustment work for eliminating the misalignment.

When the state of the optical sensor detected by the detection unit includes the presence or absence of the focus shift of the optical sensor (that is, the state in which the focused state with respect to the object to be sorted cannot be obtained), the sorting accuracy deteriorates due to the focus shift. Various processes for suppressing can be carried out. For example, the optical sorter may notify the user when a focus shift is detected.

The optical sorter injects air toward a specific object to be sorted, which is determined based on the judgment result by the judgment unit, to deviate the specific object to be sorted from the transfer path, and removes foreign matter and / or defective products. It may be provided with a sorting unit for sorting. When the transfer path extends in the first direction and the object to be sorted is transferred in the first direction with a predetermined width in the second direction orthogonal to the first direction, the sorting unit is in the second direction. In the right place for a particular object to be sorted, based on a predetermined correspondence between the position where the light associated with the object to be sorted in is detected and the position where the air should be ejected in the second direction. It may be configured to inject air from. In this case, the optical sorter may further include a first correction unit that corrects a predetermined correspondence relationship based on the amount of misalignment of the optical sensor in the second direction.

Further, the sorting unit may be configured to inject air at a predetermined timing based on a predetermined delayed injection time. The delayed injection time is the time from the detection of the light associated with a specific object to be selected until the injection of air. In this case, the optical sorter may include a second correction unit that corrects a predetermined delay injection time based on the amount of misalignment of the optical sensor in the first direction.

According to the fourth aspect of the present disclosure, in any one of the first to third embodiments, the optical sorter is based on the detection result of the marking-related light, and the detection result of the light associated with the object to be sorted. It is provided with a color correction unit configured to perform color correction on the light. According to this form, the hue of the image represented by the detection result of the optical sensor can be adjusted. When the marking is monochrome marking, at least one of linear white balance correction and dark correction may be performed as color correction. If the marking is color marking, non-linear color correction may be performed.

According to the fifth aspect of the present disclosure, in any one of the first to fourth embodiments, the optical sorter is a calibration unit configured to be able to perform calibration based on the detection result of marking-related light. It is equipped with. According to this embodiment, it is possible to satisfactorily compensate for fluctuations in the amount of light from the light source in real time during the sorting operation of the optical sorter.

According to the sixth aspect of the present disclosure, in the fifth aspect, the calibration includes adjusting the amount of light of the light source based on the detection result of the marking-related light. According to this form, it is possible to compensate for fluctuations in the amount of light from the light source without amplifying noise.

According to the seventh aspect of the present disclosure, in the fifth or sixth embodiment, the calibration includes adjusting the gain of the signal acquired by the optical sensor based on the detection result of the marking-related light. According to this form, it is possible to compensate for fluctuations in the amount of light of the light source regardless of the ability of the light source to adjust the amount of light.

According to the eighth aspect of the present disclosure, in any one of the first to seventh forms, the light source is a first light source arranged on the first side with respect to the transfer path of the object to be sorted, and the first light source. It comprises a second light source, which is located on the second side opposite to the side. The optical sensor includes at least one of a first optical sensor arranged on the first side and a second optical sensor arranged on the second side. The intermediate member has light non-transparency and substantially prevents light from passing through the intermediate member from the transfer path side and reaching the optical sensor. According to this embodiment, when the optical sensor includes the first optical sensor, the intermediate member is arranged on the first side, and the light emitted from the second light source located on the second side is intermediate. It does not pass through the member and reach the first optical sensor located on the first side. Therefore, when the marking-related light emitted from the first light source and obtained through the marking is detected by the first optical sensor, the light emitted from the second light source together with the marking-related light is emitted. It is not detected by the first optical sensor. Similarly, when the optical sensor includes a second optical sensor, the intermediate member is arranged on the second side, and the light emitted from the first light source located on the first side is transmitted through the intermediate member. Therefore, it does not reach the second optical sensor located on the second side. Therefore, when the light amount of the light source is detected based on the marking-related light, the light amount can be detected more accurately. Further, if the eighth form is combined with the second form, the state of the optical sensor can be detected more accurately. Further, when combined with the fifth embodiment, more accurate calibration can be performed based on the amount of light of the light source detected accurately. Further, if the optical sensor includes both the first optical sensor and the second optical sensor, the light amount of the first light source and the light amount of the second light source can be balanced.

According to a ninth aspect of the present disclosure, in any one of the first to eighth forms, the markings have at least one first unit area having a first color and a certain size, and a second. It has at least one second unit region having a second color different from that of one color and having a certain size. The marking is configured such that the first unit area and the second unit area are arranged one-dimensionally or two-dimensionally in a predetermined appearance pattern. A unit region is a region having a predetermined size and shape.

When the ninth embodiment is combined with the second embodiment, the optical sensor is based on, for example, whether or not a predetermined appearance pattern can be detected, or at what position a predetermined appearance pattern can be detected. The state of can be easily detected. When the first unit area and the second unit area are arranged one-dimensionally, the position shift of the optical sensor in the arrangement direction of the first unit area and the second unit area based on the marking-related light. The amount of light can be detected. When the first unit area and the second unit area are arranged two-dimensionally, based on which of the plurality of appearance patterns is detected and at which position the appearance pattern is located. The amount of misalignment and the direction of misalignment can be detected based on whether it is detected in.

When the transfer path extends in the first direction and the object to be sorted is transferred in the first direction with a predetermined width in the second direction orthogonal to the first direction, the first unit region and the second. The unit areas of may be arranged one-dimensionally in the second direction. Alternatively, the first unit area and the second unit area may be two-dimensionally arranged in the first direction and the second direction. In this case, even if the appearance patterns of the first unit area and the second unit area in the second direction are different from each other for each arrangement position of the first unit area and the second unit area in the first direction. good. According to this configuration, the amount of misalignment and the direction of misalignment can be easily detected based on the position and type of the detected appearance pattern.

According to the tenth form of the present disclosure, in the ninth form, the marking is a one-dimensional or two-dimensional code. That is, the marking is a mark created based on a predetermined system in order to represent some information. According to this embodiment, when the tenth embodiment is combined with the second embodiment, the state of the optical sensor (for example, the presence / absence of misalignment, the presence / absence of focus shift) is based on whether or not the information represented by the code can be read. Can be easily detected. Further, when the marking is a two-dimensional code, the amount of misalignment can be detected based on what kind of information is read.

According to the eleventh aspect of the present disclosure, an optical sorter is provided. This optical sorter is irradiated from a light source instead of the optical sensor of the first embodiment, and is irradiated from a first optical sensor configured to detect light associated with the object to be sorted and a light source. , A second optical sensor configured to detect marking-related light obtained through marking. This form also has the same effect as the first form. It is also possible to combine any of the second to tenth forms with the eleventh form. When the second embodiment is combined with the eleventh embodiment, the detection unit is configured to detect the state of the second optical sensor.

According to the twelfth aspect of the present disclosure, an optical sorter is provided. This optical sorter
A light source configured to illuminate the object being transferred on the transfer path, an optical sensor configured to detect the light emitted from the light source and associated with the object to be sorted, and the object to be sorted. A determination unit configured to determine the quality of the object to be sorted based on the signal acquired by the optical sensor with respect to the light associated with the object, and a light source in the direction of light irradiation from the light source to the object to be sorted. It comprises an intermediate member, located between and the transfer path, which is located at a position that does not affect the detection of light associated with the object to be sorted and has markings. The optical sensor is further configured to detect marking-related light emitted from a light source and obtained through marking. The marking comprises multiple areas. Each of the plurality of regions is configured to provide at least one or more functions for ensuring the determination performance of the determination unit based on the marking-related light. According to this optical sorter, it is possible to carry out various processes for improving the determination performance of the determination unit and, by extension, the sorting accuracy, depending on each of the plurality of regions.

According to the thirteenth aspect of the present disclosure, in the twelfth aspect, at least one function is a light amount detection function of a light source, a position shift detection function of an optical sensor, a focus shift detection function of an optical sensor, and an optical sensor. Includes at least one of the white balance confirmation functions.

According to the fourteenth aspect of the present disclosure, in the thirteenth aspect, the optical sensor includes a plurality of light receiving elements arranged linearly. Such an optical sensor may be a line sensor or an area sensor. At least a portion of the plurality of regions includes a first region configured to provide the misalignment detection function of the optical sensor. The first region comprises a small region that can be identified by the difference in color. The width of the small region in the arrangement direction of the plurality of optical elements is uniquely set according to the position in the direction intersecting the arrangement direction. The "direction intersecting the arrangement direction" may be a direction orthogonal to the arrangement direction. According to this form, the positional deviation of the optical sensor can be easily detected based on the marking-related light. Specifically, when the optical sensor is displaced in a direction intersecting the arrangement direction, the direction and amount of the deviation can be grasped based on the width of the small region detected by the optical sensor. Further, when the optical sensor is displaced in the arrangement direction, the direction and amount of the deviation can be grasped based on the positions of the start point and / or the end point of the small region detected by the optical sensor. The fourteenth embodiment can also be implemented independently of the twelfth embodiment. For example, as marking, only the above small area may be used alone.

According to the fifteenth aspect of the present disclosure, in the thirteenth or fourteenth aspect, at least a part of the plurality of regions includes a second region configured to provide a focus shift detection function. The second region comprises a small region that can be identified by the difference in color. According to this form, the focus shift of the optical sensor can be easily detected. For example, the focus shift of the optical sensor may be detected based on the detection status of the edge representing the boundary of the small region in the image data of the marking-related light corresponding to the second region. In this case, if a predetermined degree of sharp edge is detected, it may be determined that the focus shift has not occurred, and if the sharp edge is not detected, the focus shift has occurred. May be determined. Alternatively, the focus shift of the optical sensor may be detected based on the detection status of a small region in the image data of the marking-related light corresponding to the second region. In this case, for example, if a small area having a small size (for example, width) is set and the small area is detected, it may be determined that no focus shift has occurred, and the small area is detected. If this is not the case, it may be determined that a focus shift has occurred. Further, the small area may be in the form of a line. For example, the second region may have a first line and a second line thinner than the first line. In this case, the first line and the second line can detect the first line by the optical sensor when the optical sensor is in focus at the detection position of the object to be sorted, but detect the second line. It may not be possible and may be set to a thickness that allows the optical sensor to detect both the first line and the second line when the optical sensor is in focus at the marking position. The fifteenth embodiment can also be implemented independently of the twelfth embodiment. For example, as marking, only the second region may be used alone.

According to one embodiment of the present disclosure, the optical sensor is a line sensor or an area sensor having a plurality of light receiving elements arranged in a straight line. The intermediate member is arranged at a position that does not overlap with the transfer path when viewed in an arbitrary direction orthogonal to the direction in which the plurality of light receiving elements are arranged. The plurality of light receiving elements detect the light associated with the object to be sorted in transit but do not detect the marking-related light, and the light receiving element does not detect the light associated with the object to be sorted in transfer but are related to marking. Includes a light receiving element that detects light.

It is a schematic diagram which shows the schematic structure of the optical sorter according to 1st Embodiment. It is a schematic diagram which shows the positional relationship between a light source, an intermediate member, and an optical sensor. It is sectional drawing of the intermediate member. It is a figure which shows an example of the marking which an intermediate member has. It is a figure which shows the marking by 2nd Embodiment. It is a chart which shows the example of various markings.

FIG. 1 is a schematic diagram showing a schematic configuration of an optical sorter (hereinafter, simply referred to as a sorter) 10 as a first embodiment. In the present embodiment, the sorter 10 uses rice grains (more specifically, brown rice or polished rice) as the object to be sorted 90 to foreign substances (for example, pebbles, mud, glass pieces, etc.) and defective products (for example, immature grains). , Colored grains, etc.) are used to sort out. However, the material to be sorted 90 is not limited to brown rice or polished rice, and may be any granular material. For example, the material to be sorted 90 may be paddy, wheat grains, beans (soybeans, chickpeas, green soybeans, etc.), resin (pellets, etc.), rubber pieces, or the like.

As shown in FIG. 1, the sorting machine 10 includes an optical detection unit 20, a storage tank 71, a feeder 72, a chute 73, a non-defective product discharge gutter 74, a defective product discharge gutter 75, a sorting unit 76, and a controller. It is equipped with 80 and. The controller 80 controls the overall operation of the sorter 10. The controller 80 also functions as a determination unit 81, a detection unit 82, a first correction unit 83, a second correction unit 84, a color correction unit 85, and a calibration unit 86. The function of the controller 80 may be realized by the CPU executing a predetermined program, may be realized by a dedicated circuit, or may be realized by a combination thereof. Each function of the controller 80 may be realized by one integrated device. For example, each function of the controller 80 may be realized by one CPU. Alternatively, each function of the controller 80 may be distributed in at least two devices. The details of the function of the controller 80 will be described later.

The storage tank 71 temporarily stores the object to be sorted 90. The feeder 72 supplies the sorted object 90 stored in the storage tank 71 onto the chute 73 as an example of the sorted object transfer means. The object 90 supplied onto the chute 73 slides downward on the chute 73 and falls from the lower end of the chute 73. The chute 73 has a predetermined width that allows a large number of objects to be sorted 90 to be dropped at the same time. In the following description, the direction in which the transfer path 95 of the object to be sorted 90 (in other words, the fall trajectory of the object to be sorted 90) after falling from the chute 73 extends is also referred to as the first direction D1. Further, the width direction of the chute 73 (in other words, the direction orthogonal to the falling direction of the object to be sorted 90 on the bottom surface of the chute 73) is also referred to as a second direction D2. The second direction D2 is orthogonal to the first direction D1.

The optical detection unit 20 irradiates the object to be sorted 90 that has slipped off the chute 73 with light, and the light associated with the object to be sorted 90 (specifically, the transmitted light transmitted through the object to be sorted 90 and the transmitted light). , The reflected light reflected by the object to be sorted 90) is detected. The output from the optical detection unit 20, that is, the analog signal representing the detected light intensity, is amplified by an AC / DC converter (not shown) with a predetermined gain, and further converted into a digital signal. This digital signal (in other words, the gradation value corresponding to the analog signal) is input to the controller 80. Based on the input light detection result (that is, an image), the controller 80 determines whether the object to be sorted 90 is a non-defective product (that is, rice grains with relatively high quality) or a foreign substance as a process of the determination unit 81. It is determined whether the product is (that is, not a grain of rice) or a defective product (that is, a grain of rice with relatively low quality). This determination is made for each of the objects to be sorted 90. Any known determination method can be adopted for this determination. This determination is typically made by comparing the gradation value of the image data with a predetermined threshold value.

The object to be sorted 90 determined to be a foreign substance or a defective product is sorted by the sorting unit 76. Specifically, the sorting unit 76 includes an ejector 77 that injects air 78 toward the object to be sorted 90. The object 90 determined to be a foreign substance or a defective product is blown off by the air 78, deviates from the drop trajectory from the chute 73 (that is, the transfer path 95), and is guided to the defective product discharge gutter 75 (FIG. 1). As the object to be sorted 91). On the other hand, the air 78 is not injected into the object to be sorted 90, which is determined to be a non-defective product. Therefore, the object to be sorted 90 determined to be a non-defective product is guided to the non-defective product discharge gutter 74 without changing the fall trajectory (shown as the product to be sorted 92 in FIG. 1).

Hereinafter, the details of the functions of the optical detection unit 20 and the controller 80 will be described. As shown in FIG. 1, the optical detection unit 20 includes a first light source 30a, a first optical sensor 40a, a second light source 30b, and a second optical sensor 40b. The first light source 30a and the first optical sensor 40a are arranged on one side (also referred to as the front side) with respect to the transfer path 95 of the object 90 to be sorted. The second light source 30b and the second optical sensor 40b are arranged on the other side (also referred to as the rear side) with respect to the transfer path 95 of the object 90 to be sorted. The "front side" may be regarded as an example of the "first side" in the claims, and the "rear side" may be regarded as an example of the "second side" in the claims. Conversely, the "front side" may be regarded as an example of the "second side" in the claims, and the "rear side" may be regarded as an example of the "first side" in the claims. ..

The first light source 30a irradiates the object 90 being transferred (that is, falling from the chute 73) on the transfer path 95 with light 31a. Similarly, the second light source 30b irradiates the object 90 being transferred with light 31b. The first light source 30a is a light source unit in which a plurality of light emitting elements 32a are mounted on a single substrate. In this embodiment, the LED is used as the light emitting element 32a. Therefore, the light emitting element 32a is also referred to as an LED 32a. The plurality of LEDs 32a include an LED that emits red light, an LED that emits blue light, and an LED that emits green light. The second light source 30b has the same configuration as the first light source 30a, and includes a plurality of LEDs 32b.

In FIG. 1, the number of each of the first light source 30a and the second light source 30b is shown to be one, but at least one of the first light source 30a and the second light source 30b is plural. There may be. For example, two first light sources 30a may be arranged on the upper side and the lower side of the detection position on the transfer path 95, respectively. Similarly, two second light sources 30b may be arranged on the upper side and the lower side of the detection position on the transfer path 95, respectively.

The first optical sensor 40a and the second optical sensor 40b are irradiated from the first light source 30a and the second light source 30b, and detect the light associated with the object 90 to be sorted. Specifically, the first optical sensor 40a on the front side is irradiated from the first light source 30a on the front side and is irradiated from the light 31a reflected by the object 90 to be sorted and from the second light source 30b on the rear side. , The light 31b transmitted through the object to be sorted 90, and the light 31b can be detected. The second optical sensor 40b on the rear side is irradiated from the second light source 30b on the rear side and reflected by the object 90 to be sorted, and is irradiated from the first light source 30a on the front side to be sorted 90. The light 31a transmitted through the light source can be detected.

The first optical sensor 40a is, in the present embodiment, a line sensor having a plurality of light receiving elements 41a arranged in a straight line. However, the first optical sensor 40a may be an area sensor. The plurality of light receiving elements 41a are arranged in the second direction D2 (that is, the width direction of the chute 73). Therefore, the first optical sensor 40a can simultaneously image a large number of objects to be sorted 90 transferred over a predetermined width of the chute 73. Further, the first optical sensor 40a is a color CCD sensor in the present embodiment, and can detect red light, green light, and blue light individually. However, the first optical sensor 40a may be another type of sensor such as a color CMOS sensor. In the present embodiment, the second optical sensor 40b has the same configuration as the first optical sensor 40a, and includes a plurality of light receiving elements 41b arranged in the second direction D2. However, the first optical sensor 40a and the second optical sensor 40b may have different configurations from each other.

The optical detection unit 20 further includes

transparent members

21a and 21b. The transparent member 21a partitions the first light source 30a, the first optical sensor 40a, and the transfer path 95 on the front side. As a result, the first light source 30a, the first optical sensor 40a, and the transfer path 95 are isolated from each other, and dust scattered from the transfer path 95 adheres to the first light source 30a and the first optical sensor 40a. Is prevented. Similarly, the transparent member 21b partitions the second light source 30b, the second optical sensor 40b, and the transfer path 95 on the rear side.

The optical detection unit 20 further includes intermediate members 50 on the front side and the rear side, respectively. The intermediate member 50 on the front side is arranged at a position between the first light source 30a and the transfer path 95 in the irradiation direction of the light 31a from the first light source 30a to the object 90 to be sorted. The intermediate member 50 on the rear side is arranged between the second light source 30b and the transfer path 95 in the irradiation direction of the light 31b from the second light source 30b to the object 90 to be sorted.

FIG. 2 is a schematic view showing the positional relationship between the first light source 30a and the second light source 30b, the intermediate member 50, and the first optical sensor 40a and the second optical sensor 40b in the second direction D2. Is. Since the positional relationship shown is the same on the front side and the rear side, the front side will be mainly described below. As shown in FIG. 2, on the front side, a plurality of (18 in the illustrated example) light emitting elements 32a are arranged in the second direction D2 in which the plurality of light receiving elements 41a of the first optical sensor 40a are arranged. ing.

“V1” shown in FIG. 2 represents the total field of view of the first optical sensor 40a in the second direction D2. Further, "V2" shown in FIG. 2 indicates a raw material field of view, that is, a range in which the object to be sorted 90 can be imaged. The width of the raw material field of view V2 corresponds to the width of the chute 73 (in other words, the width of the transfer path 95). The plurality of light receiving elements 41a are arranged so as to extend outward from the raw material field of view V2 in the second direction D2. As a result, the non-raw material field of view V3 of the first optical sensor 40a is secured on both sides of the raw material field of view V2 in the second direction D2.

The intermediate member 50 is arranged in the region of the transparent member 21a corresponding to the non-raw material field of view V3. That is, the intermediate member 50 is arranged at a position that does not affect the detection of the light associated with the object to be sorted 90 by the first optical sensor 40a. In other words, this position is a position that does not overlap with the transfer path 95 when viewed in any direction orthogonal to the second direction D2. In this embodiment, the intermediate member 50 is arranged on both sides of the transfer path 95 in the second direction D2.

This intermediate member 50 on the front side reflects the light 31a emitted from the first light source 30a on the front side. The light 31a reflected by the intermediate member 50 is detected by the first optical sensor 40a (more specifically, the light receiving element 41a corresponding to the non-raw material field of view V3). Since the intermediate member 50 is located outside the second direction D2 from the boundary between the raw material field of view V2 and the non-raw material field of view V3, the reflected light in the intermediate member 50 is a light receiving element corresponding to the raw material field of view V2. It is not detected by 41a. On the contrary, the light associated with the object to be sorted 90 is not detected by the light receiving element 41a corresponding to the non-raw material field of view V3. Similarly, the intermediate member 50 on the rear side reflects the light 31b emitted from the second light source 30b on the rear side. The light 31b reflected by the intermediate member 50 is detected by the second optical sensor 40b (more specifically, the light receiving element 41b corresponding to the non-raw material field of view V3).

As is clear from this description, the first optical sensor 40a is shared with the detection of the light associated with the object 90 to be sorted and the detection of the light 31a reflected by the intermediate member 50. Similarly, the second optical sensor 40b is shared with the detection of the light associated with the object 90 to be sorted and the detection of the light 31b reflected by the intermediate member 50.

In the present embodiment, the intermediate member 50 is in the form of a sheet-like member that can be attached to the

transparent members

21a and 21b. That is, the intermediate member 50 is a sheet-like member having an adhesive on one side. Therefore, the device configuration of the sorter 10 can be simplified. In addition, it is easy to manufacture and the manufacturing cost is low. However, the intermediate member 50 can be realized in any form. For example, the intermediate member 50 may be a plate-shaped member. In this case, the intermediate member 50 may be arranged apart from the

transparent members

21a and 21b.

FIG. 3 is a cross-sectional view of the intermediate member 50. FIG. 3 shows an intermediate member 50 on the rear side attached to the transparent member 21b. As shown in the figure, the intermediate member 50 on the rear side has a two-layer structure. Specifically, the intermediate member 50 includes a first layer 51 located on the transfer path 95 side and a second layer 52 located on the opposite side of the transfer path 95. The first layer 51 has a light impermeable property. Therefore, in the first layer 51 of the intermediate member 50 on the rear side, the light 31a from the first light source 30a on the front side passes through the intermediate member 50 from the transfer path 95 side and reaches the second optical sensor 40b. Substantially prevent you from doing so. Although not shown, similarly, the intermediate member 50 on the front side attached to the transparent member 21a is also opposite to the first layer 51, which is located on the transfer path 95 side and has light translucency, and the transfer path 95. It has a second layer 52 located on the side. Therefore, in the first layer 51 of the intermediate member 50 on the front side, the light 31b from the second light source 30b on the rear side passes through the intermediate member 50 from the transfer path 95 side and reaches the first optical sensor 40a. Substantially prevent you from doing so.

The second layer 52 is at least partially formed of a light-reflecting material. The second layer 52 of the intermediate member 50 on the front side reflects the light 31a emitted from the first light source 30a, and the second layer 52 of the intermediate member 50 on the rear side irradiates from the second light source 30b. The light 31b to be generated is reflected.

In the present embodiment, as shown in FIG. 3, the intermediate member 50 is arranged on the side opposite to the transfer path 95 with respect to the

transparent members

21a and 21b. Therefore, the intermediate member 50 is not affected by the dust generated by the transfer of the object to be sorted 90. Moreover, the exposed surface of the first layer 51 (that is, the surface opposite to the second layer 52) becomes an adhesive surface with the

transparent members

21a and 21b of the intermediate member 50, and the exposed surface of the second layer 52 (that is, that is). , The reflective surface that reflects the light 31b) does not have an adhesive. Therefore, there is no possibility that the adhesive impairs the reflective performance of the second layer 52. However, the intermediate member 50 may be arranged on the transfer path 95 side with respect to the

transparent members

21a and 21b. Even in this case, the reflective surface of the second layer 52 is in close contact with the

transparent members

21a and 21b, so that it is not affected by dust.

The intermediate member 50 (more specifically, the second layer 52) has a marking 53 on its surface (specifically, the surface opposite to the transfer path 95). Therefore, each of the light 31a reflected by the intermediate member 50 and detected by the first optical sensor 40a and the light 31b reflected by the intermediate member 50 and detected by the second optical sensor 40b are marked 53. It can be said that it is the light obtained through the above (in other words, the reflected light at the marking 53). Such light obtained via the marking 53 is also referred to as marking-related light. The marking 53 may be printed on the surface of the second layer 52, for example.

FIG. 4 is a diagram showing an example of the marking 53. FIG. 4 shows a marking 53 viewed in a direction orthogonal to the first direction D1 and the second direction D2. In the example shown in FIG. 4, the marking 53 is composed of a plurality of unit regions UA. The unit area UA has a predetermined size and shape. In FIG. 4, the size and shape of the unit area UA are shown in the lower right. The unit area UA is a square in the example shown in FIG. 4, but can have any shape. The marking 53 includes a first unit region 54 having a first color and a second unit region 55 having a second color. In this embodiment, the first color is black and the second color is white. The first unit region 54 and the second unit region 55 are configured to be two-dimensionally arranged in the first direction D1 and the second direction D2 in a predetermined appearance pattern.

In the present embodiment, as shown in FIG. 4, the appearance pattern of the first unit region 54 and the second unit region 55 in the second direction D2 is the first unit region 54 and the first unit region 54 in the first direction D1. It differs depending on the arrangement position of the unit areas 55 of 2 (shown as positions P1 to P19 in FIG. 4).

According to the above-mentioned sorting machine 10, it is possible to carry out various processes for improving the sorting accuracy by using the marking-related light. Hereinafter, such processing will be described. First, the controller 80 is configured to detect the states of the first optical sensor 40a and the second optical sensor 40b based on the detection result of the marking-related light as a process of the detection unit 82. The state of the first optical sensor 40a on the front side is detected based on the marking-related light obtained through the marking 53 of the intermediate member 50 attached to the transparent member 21a on the front side. The state of the second optical sensor 40b on the rear side is detected based on the marking-related light obtained through the marking 53 of the intermediate member 50 attached to the transparent member 21b on the rear side.

The states of the first optical sensor 40a and the second optical sensor 40b detected by the detection unit 82 include the states related to the installation positions of the first optical sensor 40a and the second optical sensor 40b. The state related to such an installation position includes the presence / absence of misalignment of the first optical sensor 40a and the second optical sensor 40b, the amount of misalignment, the direction of misalignment, and the presence / absence of focus misalignment. At least one may be included.

The presence or absence of misalignment, the amount and direction of misalignment can be detected, for example, as follows. As a specific example, it is assumed that when the first optical sensor 40a is arranged at a normal position, the region on the line L1 is imaged by the first optical sensor 40a. In this case, when the appearance pattern detected based on the marking-related light is the appearance pattern of the arrangement position P10, it can be detected that the first optical sensor 40a is not deviated from the first direction D1. On the other hand, when the appearance pattern detected based on the marking-related light is the appearance pattern of the alignment position P12, the first optical sensor 40a is aligned from the first direction D1 (more specifically, the alignment position P1). It can be seen that the line L2 is displaced in the direction toward the position P19). The amount of deviation at this time may be about two sizes of the unit region UA (more accurately, a distance larger than the length of one side of the unit region UA and smaller than twice the length). Detected.

Further, any of the plurality of light receiving elements 41a (which are arranged in the second direction D2) of the first optical sensor 40a detects the appearance pattern of any of the arrangement positions P1 to P19. Based on the above, it is possible to detect to which side and how much the first optical sensor 40a is deviated in the second direction D2.

Each appearance pattern of the arrangement positions P1 to P19 may be stored in the memory of the controller 80 at the time of manufacturing the sorter 10. Further, it is detected from the marking-related light detected by the first optical sensor 40a and the second optical sensor 40b after the first optical sensor 40a and the second optical sensor 40b are attached in place in the manufacturing stage of the sorter 10. The appearance pattern to be performed may be stored in the memory of the controller 80 as an appearance pattern corresponding to the first optical sensor 40a and the second optical sensor 40b in the normal positions. Similarly, the position of the light receiving element that has detected the appearance pattern may be stored in the memory of the controller 80 as the detection position corresponding to the first optical sensor 40a and the second optical sensor 40b at the normal positions. ..

The presence or absence of focus shift can be detected, for example, as follows. In one embodiment, first, the image data (RAW data) of the marking-related light is binarized. In this binarization, the pixel value corresponding to gray generated due to the focus shift is converted into the pixel value corresponding to white. Then, by pattern matching, it is determined whether or not the appearance pattern represented by the binarized image matches any of the plurality of appearance patterns stored in advance (that is, the appearance patterns of the arrangement positions P1 to P19). Will be done. When the appearance pattern represented by the image obtained by binarization does not match any of the appearance patterns stored in advance, it can be detected that the focus shift has occurred. In the alternative embodiment, the out-of-focus may be detected based on whether or not a predetermined degree of sharp edge is detected in the image data of the marking-related light.

In the present embodiment, since the intermediate member 50 is arranged on both sides of the transfer path 95 in the second direction D2, the first optical sensor 40a or the second optical sensor 40b is in the second direction D2. Even if the arrangement is slightly offset on one side to the extent that it does not affect the sorting accuracy, and the displacement is large enough to affect the sorting accuracy on the other side, the misalignment is caused. It can be detected reliably.

When the position shift or the focus shift of the first optical sensor 40a or the second optical sensor 40b is detected by the detection unit 82, the controller 80 may notify the user of the detected content via the notification unit 88. good. The notification unit 88 may be in the form of a screen, a speaker, a light, or the like of the operation panel of the sorting machine 10. That is, the notification may be performed in the form of a display on the screen, a warning sound, lighting of a light, or the like. According to this configuration, the user can notice an abnormality in the position or focus state of the first optical sensor 40a or the second optical sensor 40b at an early stage, and can perform work for eliminating the abnormality. As a result, even though the abnormality has occurred, the sorting operation of the sorting machine 10 is continued, and the deterioration of the sorting accuracy is suppressed. Further, when the controller 80 is configured to notify the direction and amount of the misalignment, the user may use the first optical sensor 40a or the second optical sensor 40a when performing the adjustment work for eliminating the misalignment. It is easy to grasp in which direction and how much the installation position of the optical sensor 40b should be moved. When the first optical sensor 40a and the second optical sensor 40b have an autofocus function, the focus shift may be automatically eliminated when the focus shift is detected.

In the present embodiment, when the misalignment of the first optical sensor 40a or the second optical sensor 40b is detected, the controller 80 further performs a process for suppressing deterioration of sorting accuracy due to the misalignment. It can be done automatically. This process is executed as at least one of the first correction unit 83 and the second correction unit 84.

First, the processing of the first correction unit 83 will be described. In the sorting unit 76, a plurality of valves (not shown) controlling the injection of the air 78 are arranged in the second direction D2 in order to simultaneously sort the plurality of objects 90 to be simultaneously transferred over the width of the chute 73. Has been done. Then, one of the valves is assigned to each of the detection positions of the object to be sorted 90 in the second direction D2 of the first optical sensor 40a and the second optical sensor 40b. In other words, the position where the light associated with the object 90 to be sorted in the second direction D2 is detected (hereinafter, also referred to as the detection position) and the position where the air 78 in the second direction D2 should be ejected (hereinafter, also referred to as the detection position). , Also called the injection position) and the correspondence relationship is predetermined. When it is determined that one object to be sorted 90 is a foreign substance or a defective product, air 78 is injected from the injection position corresponding to the detection position of the one object to be sorted 90.

The controller 80 corresponds to the detection position and the injection position based on the amount of the positional deviation of the first optical sensor 40a or the second optical sensor 40b in the second direction D2 as the processing of the first correction unit 83. Correct the relationship. More specifically, when the positional deviation of the first optical sensor 40a or the second optical sensor 40b occurs in the second direction D2, the detection position in the correspondence between the detection position and the injection position is the position. It will be displaced in the direction of displacement by the amount of displacement. Therefore, correction is performed to shift the injection position corresponding to the detection position by the amount of the misalignment in the direction opposite to the direction of the misalignment. As a result, the correspondence will return to the original normal state. According to the first correction unit 83, even if the position of the first optical sensor 40a or the second optical sensor 40b is displaced in the second direction D2, the sorting accuracy is deteriorated due to the positional deviation. Can be automatically suppressed.

Next, the processing of the second correction unit 84 will be described. In the first direction D1, the position where the trajectory of the object to be sorted 90 is changed by the air 78 from the ejector 77 (hereinafter, also referred to as the trajectory change position) is detected by the first optical sensor 40a and the second optical sensor 40b. Below the position. Therefore, the sorting unit 76 detects the foreign matter or the defective product by the first optical sensor 40a or the second optical sensor 40b, and then airs the foreign matter or the defective product toward the foreign matter or the defective product at a timing delayed by a predetermined time. It is configured to inject 78. This time difference is also commonly referred to as the delayed injection time. The delayed injection time is predetermined. The delayed irradiation time may be predetermined as a constant value, or may be variable based on arbitrary parameters (for example, the type of the object to be sorted 90, the actually measured drop speed of the object to be sorted 90, etc.). It may be predetermined.

As a process of the second correction unit 84, the controller 80 corrects the delay injection time described above based on the amount of misalignment of the first optical sensor 40a or the second optical sensor 40b in the first direction D1. .. For example, when the first optical sensor 40a or the second optical sensor 40b is displaced downward in the first direction D1 from the normal position, the first is compared with the case where the positional deviation does not occur. The distance between the detection position of the object to be sorted 90 by the optical sensor 40a or the second optical sensor 40b and the trajectory change position becomes small. Therefore, the controller 80 shortens the delayed injection time according to the amount of deviation in the first direction D1. On the contrary, when the first optical sensor 40a or the second optical sensor 40b is displaced upward in the first direction D1 from the normal position, the controller 80 adjusts to the deviation amount in the first direction D1. The delayed injection time is extended accordingly.

The delayed injection time may be corrected by using a function whose variable is the amount of misalignment of the first optical sensor 40a or the second optical sensor 40b in the first direction D1. This function may be predetermined experimentally and stored in the memory of the controller 80. Alternatively, the distance between the normal detection position of the object 90 to be sorted by the first optical sensor 40a or the second optical sensor 40b and the trajectory change position, the tilt angle of the chute 73, and the transfer speed of the object 90 to be sorted (this is It may be actually measured or predetermined by an experiment), and it is physically based on the amount of misalignment of the first optical sensor 40a or the second optical sensor 40b in the first direction D1. It may be calculated by various calculations. According to the second correction unit 84, even if the position of the first optical sensor 40a or the second optical sensor 40b is displaced in the first direction D1, the sorting accuracy is deteriorated due to the positional deviation. Can be automatically suppressed.

In the present embodiment, the amount of misalignment is detected on both sides of the transfer path 95 in the second direction D2. Therefore, when the detection amount on one side and the detection amount on the other side are different, for example, the processing of the first correction unit 83 and the second correction unit 84 is performed using the average value of the detection amounts on both sides. It may be done.

The processing of the detection unit 82, the first correction unit 83, and the second correction unit 84 described above may be executed as initial adjustment at the time of manufacturing or initial use of the sorter 10. Alternatively, these processes may be performed at predetermined timings when the sorter 10 is used (that is, during the sorting operation). The installation positions of the first optical sensor 40a and the second optical sensor 40b may shift due to an impact received during transportation of the sorter 10, but in the latter case, such post-shipment position may occur. It can also cope with misalignment. Further, the processing of the first correction unit 83 and the second correction unit 84 may be automatically executed when the misalignment is detected, may be executed manually, or may be executed manually. It may be executed when the user operation is not performed for a predetermined period after notifying the occurrence of the misalignment.

Further, in the present embodiment, as a process of the color correction unit 85, the controller 80 performs color correction on the detection result of the light associated with the object to be sorted 90 based on the detection result of the marking-related light. It is composed. Specifically, the controller 80 can perform dark correction based on the image pickup result of the black first unit region 54. Specifically, a representative value of the color gradation value of the image data in the first unit region 54 (for example, the average value of the color gradation value) can be used as the black level.

Further, the controller 80 can perform white balance correction based on the image pickup result of the white second unit region 55. For example, when the image is represented by 256 gradations, the representative value of the color gradation value of the image data in the first unit area 54 corresponds to the gradation value 0, and the image data in the second unit area 55. A linear white balance correction may be performed so that the representative value of the color gradation value of is corresponding to the gradation value 255. Such a color correction process may be performed, for example, at the start of the sorting operation of the sorting machine 10. According to the color correction unit 85, when the first optical sensor 40a and the second optical sensor 40b, or the first light source 30a and the second light source 30b are replaced, the light detection performance before the replacement is brought closer. Can be done. This point is particularly effective when the model number of the part before replacement has been discontinued and a substitute is newly installed.

Further, according to the above-mentioned sorter 10, the amount of light of the first light source 30a and the second light source 30b is detected based on the marking-related light (more specifically, the image pickup result of the second unit region 55). can. Since the intermediate member 50 having the marking 53 is arranged at a position that does not affect the detection of the light associated with the object to be sorted 90, the first light source 30a and the second light source 30b are arranged during the sorting operation of the sorting machine 10. The amount of light can be detected in real time. Moreover, no additional optical sensor is required to detect the amount of light of the first light source 30a and the second light source 30b.

As described above, the first layer 51 of the intermediate member 50 has light translucency. Therefore, when the marking-related light is detected by the first optical sensor 40a on the front side, the light 31b from the second light source 30b on the rear side is combined with the light 31a from the first light source 30a on the front side. Is not detected by the first optical sensor 40a. Therefore, the amount of light of the first light source 30a can be accurately detected without being affected by the light 31b emitted from the second light source 30b. Similarly, the amount of light of the second light source 30b can be accurately detected without being affected by the light 31a emitted from the first light source 30a. In other words, even if the light amount fluctuates in only one of the first light source 30a and the second light source 30b, the light amount of the first light source 30a and the light amount of the second light source 30b are separately accurate. Can be detected. The light translucency of the first layer 51 also enables more accurate detection of the shape of the marking 53 and, by extension, more accurate detection of the states of the first optical sensor 40a and the second optical sensor 40b. To contribute.

According to the sorter 10, the light amounts of the first light source 30a and the second light source 30b can be detected by using the intermediate member 50 on both sides of the transfer path 95 in the second direction D2. Therefore, it is easier to grasp the local tendency of the light amount of the first light source 30a and the second light source 30b as compared with the case where the light amount is detected only on one side. For example, when an abnormality in the amount of light occurs on only one side in the second direction D2, it is easy to grasp the abnormality.

In the present embodiment, in the sorting machine 10, in order to further improve the sorting accuracy, calibration and calibration are performed based on the light amounts of the first light source 30a and the second light source 30b detected by using the marking-related light. Notification can be performed. The configuration will be described below. In the present embodiment, the calibration is repeatedly executed during the sorting operation of the sorting machine 10 as a process of the calibration unit 86 of the controller 80. Specifically, the calibration unit 86 first acquires the light amounts of the first light source 30a and the second light source 30b acquired by using the marking-related light as described above. This amount of light is acquired for each RGB color component. Further, this amount of light is acquired for each of one side and the other side of the second direction D2. The acquired light amount is a statistical value (for example, average value, center) of the detection result of the white second unit region 55 among the detection results of the plurality of light receiving elements 41a or the light receiving element 41b corresponding to the non-raw material field of view V3. Value, etc.).

Next, the calibration unit 86 determines whether or not the acquired light amount is within the first range. The first range may be preset for each RGB color component. This first range is a range bounded by the first threshold value TH1 and the second threshold value TH2, and a reference value representing an ideal amount of light is included in this first range. For example, the first threshold value TH1 may be set as a value of minus 30% with respect to the reference value, and the second threshold value TH2 may be set as a value of plus 30% with respect to the reference value.

As a result of the determination, when there is a color component whose light amount is out of the first range, the controller 80 notifies the user of the light amount abnormality via the notification unit 88. According to this configuration, it is possible to notify the light amount abnormality of the first light source 30a or the second light source 30b in real time during the sorting operation of the sorting machine 10. Therefore, the user can notice the light intensity abnormality of the first light source 30a or the second light source 30b at an early stage. As a result, even though the light source abnormality has occurred, the sorting operation of the sorting machine 10 is continued, and the deterioration of the sorting accuracy is suppressed.

On the other hand, if the amount of light for all the RGB color components is within the first range, then the calibration unit 86 determines whether or not the acquired amount of light is within the second range. The second range may be preset for each RGB color component. This second range is a range bounded by the third threshold TH3 (TH1 <TH3) and the fourth threshold TH4 (TH4 <TH2), and the reference value is included in this second range. Then, as a result of the determination, if the acquired light amount is not within the second range, the calibration unit 86 executes the calibration. The calibration here is a process of adjusting the amount of light of the first light source 30a and the second light source 30b according to the detected amount of light. Specifically, the calibration unit 86 adjusts the amount of light of the corresponding light emitting elements 32a and 32b based on the detection results of the corresponding

light receiving elements

41a and 41b for each color component. Further, in the present embodiment, the light amount is detected on both sides of the transfer path 95 in the second direction D2, so that the light amount is located on one side based on the light amount detection result on one side in the second direction D2. The light amount of the light emitting elements 32a and 32b is adjusted, and similarly, the light amount of the light emitting elements 32a and 32b located on the other side is adjusted based on the light amount detection result on the other side in the second direction D2. If calibration is performed by adjusting the amount of light, it is possible to compensate for fluctuations in the amount of light of the first light source 30a and the second light source 30b without amplifying noise.

In the present embodiment, the controller 80 adjusts the amount of light of the light emitting elements 32a and 32b by PWM control. More specifically, at the time of shipment of the sorter 10, the controller 80 is set to apply a voltage to the light emitting elements 32a and 32b at a duty ratio of 50%. Then, the calibration unit 86 compensates for fluctuations in the amount of light of the light emitting elements 32a and 32b by increasing or decreasing the duty ratio. That is, when the light amount of the light emitting elements 32a and 32b is larger than the reference value, the calibration unit 86 reduces the duty ratio so that the light amount becomes the reference value, and the light amount of the light emitting elements 32a and 32b is smaller than the reference value. Occasionally, the duty ratio is increased so that the amount of light becomes a reference value. By setting the default duty ratio to less than 100%, it is possible to cope with both when the amount of light is higher than the reference value and when the amount of light is lower than the reference value. If the amount of light does not reach the reference value even if the duty ratio is changed, the controller 80 notifies via the notification unit 88.

On the other hand, if the acquired light amount is within the second range, the calibration unit 86 determines that the calibration is not executed. That is, when the fluctuation of the amount of light is small enough that it is not necessary to perform the calibration, the execution of the calibration is refrained. According to this form, the load on the controller 80 can be reduced.

According to the calibration unit 86, even if the amount of light of at least one of the first light source 30a and the second light source 30b fluctuates during the sorting operation of the sorting machine 10, the fluctuation can be compensated for in real time. Moreover, since the above-mentioned intermediate member 50 can accurately detect the light amounts of the first light source 30a and the second light source 30b separately, the calibration accuracy is also improved. Then, calibration can be performed so that the intensity of the signal acquired by the first optical sensor 40a and the intensity of the signal acquired by the second optical sensor 40b are within the same reference range. Therefore, the determination accuracy by the determination unit 81 is improved.

Further, according to the calibration unit 86, if the degree of fluctuation in the amount of light of the first light source 30a and the second light source 30b is such that the determination accuracy can be appropriately ensured by the calibration, the calibration is executed and the determination is made. If the accuracy cannot be properly ensured, an abnormality in the amount of light is notified. Therefore, appropriate measures can be taken according to the degree of fluctuation in the amount of light.

In the alternative embodiment, the calibration unit 86 executes the calibration if the detected light amount is within the first range. That is, if the difference between the detected light amount and the reference value is such that it is not necessary to notify the light amount abnormality, calibration is performed even when the difference is very small. According to this embodiment, fluctuations in the amount of light of the first light source 30a and the first optical sensor 40a can be compensated more strictly.

In a further alternative embodiment, the calibration unit 86 adjusts the gain for the signal acquired by the

light receiving elements

41a, 41b corresponding to the raw material field of view V2, instead of adjusting the light amount of the light emitting elements 32a, 32b. To perform calibration. That is, when the light amount of the light emitting elements 32a and 32b is larger than the reference value, the calibration unit 86 reduces the gain by the ratio, and when the light amount of the light emitting elements 32a and 32b is less than the reference value, the ratio is reduced. Only increase the gain. In this embodiment, the gain is changed by changing the gain in the AC / DC converter, but when the first optical sensor 40a and the second optical sensor 40b have an amplifier circuit built-in, the gain is changed. The gain of the amplifier circuit may be changed. According to this embodiment, it is possible to compensate for fluctuations in the amount of light of the first light source 30a and the second light source 30b regardless of the light amount adjusting ability of the first light source 30a and the second light source 30b.

In a further alternative embodiment, the calibration unit 86 performs calibration by combining an aspect of adjusting the amount of light of the light emitting elements 32a and 32b and an aspect of adjusting the gain. For example, the default duty ratio may be set to 100%. In this case, when the light amount of the light emitting elements 32a and 32b is larger than the reference value, the calibration unit 86 reduces the duty ratio so that the light amount becomes the reference value, and the light amount of the light emitting elements 32a and 32b is larger than the reference value. When it is small, the gain is increased by the ratio. According to this embodiment, a sufficient amount of light can be secured when the amount of light of the light emitting elements 32a and 32b is within an appropriate range. Alternatively, if the default duty ratio is set to less than 100% (for example, 90%) and the amount of light does not reach the reference value even if the duty ratio is increased to 100%, the gain is adjusted with respect to the amount of insufficient light. May be done.

The calibration process and notification process described above can be performed at any time. For example, these processes may be performed instead of or in addition to the sorting operation of the sorting machine 10 before the start of the operation of the sorting machine 10. Further, when the sorting machine 10 is configured to be able to clean the

transparent members

21a and 21b by the wiper and is configured to temporarily interrupt the sorting process for cleaning, the calibration process is performed. And the notification process may be performed at the time of the cleaning.

In the sorter 10 described above, the size of the unit region UA of the marking 53 may be set to be about the same as the size of the visual field of each of the plurality of

light receiving elements

41a and 41b. By doing so, the positional deviation of the first optical sensor 40a and the second optical sensor 40b can be detected with high accuracy. Alternatively, the size of the unit region UA may be set to about half of the minimum dimension (for example, grain thickness in the case of rice) of the object to be sorted 90 (for example, about 1.5 mm in the case of rice). .. By doing so, it is possible to detect only the positional deviation that greatly affects the sorting accuracy. Alternatively, the size of the unit region UA may be set to be equal to or more than the size of the visual field of each of the plurality of

light receiving elements

41a and 41b and to be about half or less of the minimum dimension of the object to be sorted 90.

In the alternative embodiment, various markings can be used instead of the marking 53 illustrated in FIG. For example, the marking replaces or in addition to at least one of the black first unit area 54 and the white second unit area 55 shown in FIG. 4, and other colors other than white and black. It may include a unit area. The other unit regions may include two or more types of unit regions having different colors from each other. Further, the marking may be a color marking having two or more colors other than white and black. For example, the marking may have white, black, red, green, blue, cyan, magenta, and yellow unit regions, respectively. When such color marking is used, the color correction unit 85 may be configured to perform non-linear color correction so that each gradation value of the marking image approaches a predetermined color. Further, unit regions of the same color or different colors may be spaced apart from each other, or may be adjacent to each other without a gap as in the example shown in FIG.

Further, the unit regions do not necessarily have to be arranged two-dimensionally, and may be arranged one-dimensionally only in the second direction D2. In this way, the amount of misalignment in the second direction D2 can be detected.

Furthermore, a two-dimensional code may be used as a marking. Even in this way, the same effect as that of the above-described embodiment can be obtained. The two-dimensional code may be a standardized and known code, for example, a stack type (PDF417, CODE49, etc.) or a matrix type (QR code (registered trademark), DataMatrix, VeriCode (registered trademark), etc.). There may be. Alternatively, the two-dimensional code may be independently developed.

Further, a one-dimensional code (for example, a barcode) may be used as a marking. In this case, if the markings are arranged so that the bars are lined up in the second direction D2, the amount of misalignment in the second direction D2 can be detected. When a one-dimensional or two-dimensional code is used as a marking, the state of the optical sensor (eg, misalignment, misalignment) can be easily detected based on whether the information represented by the code can be read. .. Further, when the marking is a two-dimensional code, the amount of misalignment in the first direction D1 can be detected based on what kind of information is read.

However, the marking is not limited to the above-mentioned example, and may be a single or multiple markings of any shape. For example, the marking may be a mark such as "+", "-", "■", "▲".

Hereinafter, the second embodiment will be described. The second embodiment is different from the first embodiment only in that the marking 153 is provided instead of the marking 53, and the apparatus configuration of the sorting machine 10 of the second embodiment is the same as that of the first embodiment. .. As shown in FIG. 5, the marking 153 includes a first region 154, a second region 155, and a third region 156. Each of these regions 154 to 156 provides at least one or more functions for ensuring the determination performance of the determination unit 81 based on the marking-related light. In this embodiment, each of the regions 154 to 156 provides different functions from each other. Hereinafter, regions 154 to 156 will be specifically described.

The first region 154 provides a misalignment detection function for the

optical sensors

40a and 40b. The first region 154 comprises a small black region 157. The small region 157 has a trapezoidal shape with an upper base and a lower base parallel to the second direction D2. A white left small region 158 and a right small region 159 are located on both sides of the small region 157 in the second direction D2. That is, the boundaries of the small area 157 are identified by the difference in color. The width W1 of the small region 157 in the second direction D2 is uniquely determined according to the position of the first direction D1 (that is, the direction orthogonal to the second direction D2) due to the trapezoidal shape.

Based on the marking-related light obtained based on this first region 154, it is possible to detect the presence / absence, direction, and amount of misalignment of the

optical sensors

40a and 40b. A specific example will be described below assuming that the intermediate linear region A1 is imaged by the first optical sensor 40a when the first optical sensor 40a is arranged at a normal position. When the position of the first optical sensor 40a shifts to one side of the first direction D1 and the upper linear region A2 is imaged by the first optical sensor 40a, the small area detected by the first optical sensor 40a is detected. The width W1 of the region 157 becomes larger in proportion to the amount of deviation as compared with the normal position (intermediate linear region A1). On the other hand, when the position of the first optical sensor 40a shifts to the other side in the first direction D1 and the lower linear region A3 is imaged by the first optical sensor 40a, it is detected by the first optical sensor 40a. The width W1 of the small region 157 becomes smaller in proportion to the amount of deviation as compared with the normal position (intermediate linear region A1). Therefore, the direction and amount of the positional deviation in the first direction D1 can be detected based on the width W1.

Further, the boundary between the small area 157 and the left small area 158 is orthogonal to the second direction D2 (in other words, parallel to the first direction D1). Therefore, even if the position of the first optical sensor 40a shifts to the first direction D1, the detection position of the boundary in the second direction D2 does not change. On the other hand, when the position of the first optical sensor 40a shifts in the second direction D2, the boundary (in other words, the starting point of the small region 157 in the second direction D2) corresponds to the direction of the shift and the amount of the shift. The detection position of is changed. Therefore, the direction and amount of deviation in the second direction D2 can be detected based on the detection position of the boundary.

In the alternative embodiment in which the boundary between the small area 157 and the right side small area 159 is orthogonal to the second direction D2, the boundary between the small area 157 and the right side small area 159 (in other words, the second direction D2). The direction and amount of deviation in the second direction D2 can be detected based on the detection position of the small region 157). Further, the boundary between the small area 157 and the left side small area 158 is not orthogonal to the second direction D2, and the boundary between the small area 157 and the right side small area 159 is not orthogonal to the second direction D2. In an alternative embodiment, the direction and amount of deviation in the second direction D2 can be detected based on the detection positions of both the start point and the end point of the small region 157 in the second direction D2. Although detailed description will be omitted, the misalignment detection function can be provided by the same principle by using other portions of the first region 154 (parts other than the small regions 157 to 159). Further, in another alternative embodiment, the width W1 of the small region 157 may be set to be uniquely determined according to the position of the direction intersecting the second direction D2 (hereinafter, also referred to as the intersecting direction).

The second region 155 provides a focus shift detection function for the

optical sensors

40a and 40b. The second region 155 includes a plurality of white first lines 161 and a plurality of white second lines 162. Each of the second lines 162 is thinner than any of the plurality of first lines 161.

Each of the

optical sensors

40a and 40b is initially set to be in focus at the detection position of the object to be sorted 90 (that is, the position on the transfer path 95) at any position in the second direction D2. Further, regarding the marking 153 on the front side, the thickness of the first line 161 and the second line 162 is the first when the first optical sensor 40a is in focus at the detection position of the object to be sorted 90. The first line 161 can be detected by the optical sensor 40a of the above, but the second line 162 cannot be detected due to blurring, and the first optical sensor 40a is in focus at the position of the marking 153. The optical sensor 40a of the above is set so that both the first line 161 and the second line 162 can be detected. The relationship between the marking 153 on the rear side and the second optical sensor 40b is also the same.

Based on the marking-related light obtained based on such a second region 155, when both the first line 161 and the second line 162 are not detected, and the first line 161 and the second line When both 162 are detected, it can be determined that the focus shift has occurred with respect to the detection position of the object to be sorted 90. Whether or not the first line 161 and the second line 162 can be detected may be determined, for example, by binarization processing using a threshold value based on the signals acquired by the

optical sensors

40a and 40b. Alternatively, it may be performed by an edge detection process.

The third area 156 provides a white balance confirmation function. Specifically, the third region 156 is a white region, and the current white balance setting can be confirmed from the gradation value of the marking-related light obtained based on the third region 156. Further, if necessary, the white balance is corrected so that the gradation value of the marking-related light obtained based on the third region 156 becomes an arbitrary reference value (for example, the reference value of the gradation value 255). You may. Since the third region 156 is a white region as a whole, even if the positions of the

optical sensors

40a and 40b are displaced, the white balance confirmation function can be provided without being affected by the position.

At least one of the regions 154 to 156 may provide a light amount detecting function of the

light sources

30a and 30b. That is, the amount of light of the

light sources

30a and 30b may be detected based on the marking-related light obtained through at least one of the regions 154 to 156. In this case, the processing of the calibration unit 86 may be executed as in the first embodiment based on the detected amount of light. In this case, the calibration unit 86 may adjust the amount of light by the aperture of the lenses of the

optical sensors

40a and 40b. Alternatively, the calibration unit 86 may detect that at least a part of the light emitting elements 32a and 32b is in a non-lighting state due to a failure, deterioration, or the like as a light amount abnormality based on the detected light amount.

FIG. 6 shows examples of various markings that can be used in place of marking 153. Examples 1 to 4 are examples of markings that can provide a misalignment detection function and a white balance confirmation function, and Examples 5 to 8 provide a focus shift detection function in addition to the misalignment detection function and the white balance confirmation function. An example of markings that can be provided. In Examples 5 to 8, as described above, the focus shift detection function is added by the combination of the relatively thick line and the relatively thin line. Examples 1 to 3, 5 to 8 are monochrome markings in which only black and white are used, and Example 4 is color marking having a plurality of colors other than black and white. However, with respect to Examples 1 to 8 shown in FIG. 6, the marking color is not particularly limited, and any number and type of colors may be used for marking. This point is the same for the marking 153 shown in FIG. Further, the outer and inner shapes of the marking are not limited to the various examples shown in FIGS. 5 and 6, and can be arbitrarily set as long as they can provide at least a part of the above-mentioned functions.

Although the embodiments of the present disclosure have been described above, the above-described embodiments are for facilitating the understanding of the present teaching and do not limit the present invention. The present invention can be modified and improved without departing from the spirit thereof, and the present invention includes equivalents thereof. In addition, any combination of claims and any combination of each component described in the specification, or any omission may be made to the extent that at least a part of the above-mentioned problems can be solved or at least a part of the effect is exhibited. It is possible.

For example, the first light source 30a and the second light source 30b may be configured by any type of light emitting element instead of the LED. The light emitting element may be, for example, a fluorescent lamp, EL, or the like. Further, the sorter 10 may include a light source that irradiates near infrared rays in place of or in addition to the

first light sources

30a and 30b. In this case, an additional intermediate member having the same function as the intermediate member 50 may be provided for the near-infrared light source, and calibration processing and notification processing may be performed on the near-infrared light source. Further, an additional optical sensor for detecting near-infrared light may be provided. In this case, the detection unit 82, the first correction unit 83, and the second correction unit 84 may be processed with respect to the additional optical sensor. Further, the light source used in the sorter 10 is not limited to the configuration that emits visible light or near-infrared light exemplified above, but emits electromagnetic waves of arbitrary wavelengths (in other words, light in a broad sense). It may be configured to do so. In this case, any type of sensor may be employed to detect the electromagnetic waves emitted by the light source, and for at least one of the light source and the sensor, an intermediate having the same function as the intermediate member 50. Members may be provided.

Further, the first layer 51 of the intermediate member 50 may be omitted. Alternatively, the intermediate member 50 may include a single-layer region and a multi-layer region. Further, at least a part of the detection unit 82, the first correction unit 83, the second correction unit 84, the color correction unit 85, and the calibration unit 86 may be omitted. Alternatively, at least a part of the above-mentioned notification process may be omitted.

Further, one of the first optical sensor 40a and the second optical sensor 40b may be omitted, or one of the first light source 30a and the second light source 30b may be omitted. With such omission, the light associated with the object to be sorted 90 may be one of the reflected light and the transmitted light. On the contrary, the number of light sources may be any number of 2 or more on the front side and may be any number of 2 or more on the rear side. Similarly, the number of optical sensors may be any number of 2 or more on the front side and may be any number of 2 or more on the rear side. The number of each of the light source and the optical sensor may be the same on the front side and the number on the rear side, or may be different from each other. Further, the total number of light sources on the front side and the rear side and the total number of optical sensors on the front side and the rear side may be the same number or different from each other.

Further, the number of intermediate members 50 installed can be any number of 1 or more.

Further, the sorter 10 may include an additional optical sensor for detecting marking-related light in addition to the first optical sensor 40a and the second optical sensor 40b. In this case, the first optical sensor 40a and the second optical sensor 40b are used only for detecting the light associated with the object 90 to be sorted.

10 ... Optical sorter 20 ...

Optical detection unit

21a, 21b ... Transparent member 30a ... First light source 30b ... Second

light source

31a, 31b ... Light 32a, 32b. .. Light source 40a ... First optical sensor 40b ... Second

optical sensor

41a, 41b ... Light receiving element 50 ... Intermediate member 51 ... First layer 52 ... Second Layer 53 ... Marking 54 ... First unit area 55 ... Second unit area 71 ... Storage tank 72 ... Feeder 73 ... Shoot 74 ... Good product discharge gutter 75. .. Defective product discharge gutter 76 ... Sorting unit 77 ... Ejector 78 ... Air 80 ... Controller 81 ... Judgment unit 82 ... Detection unit 83 ... First correction unit 84. .. 2nd correction unit 85 ... color correction unit 86 ... calibration unit 88 ...

notification unit

90, 91, 92 ... object to be sorted 95 ... transfer path 153 ... marking 154 ... first area 155 ... second area 156 ... third area 157 ... small area 158 ... left side small area 159 ... right side small area 161 ... first Line 162 ... 2nd line D1 ... 1st direction D2 ... 2nd direction V1 ... Total field of view of the 1st optical sensor and the 2nd optical sensor V2 ... 1st Raw material field of view of optical sensor and second optical sensor V3 ... Non-raw material field of view of first optical sensor and second optical sensor

Claims

It ’s an optical sorter,
A light source configured to illuminate the object being transferred on the transfer path, and
An optical sensor configured to detect light emitted from the light source and associated with the object to be sorted.
A determination unit configured to determine a foreign object and / or a defective product for the object to be sorted based on a signal acquired by the optical sensor with respect to the light associated with the object to be sorted.
It is arranged at a position between the light source and the transfer path in the direction of irradiation of the light from the light source to the object to be sorted, and at a position that does not affect the detection of the light associated with the object to be sorted. Equipped with an intermediate member with markings,
The optical sensor is an optical sorter configured to detect marking-related light emitted from the light source and obtained through the marking.
The optical sorter according to claim 1.
An optical sorter including a detection unit configured to detect the state of the optical sensor based on the detection result of the marking-related light.
The optical sorter according to claim 1 or 2.
An optical sorter including a calibration unit configured to be able to perform calibration based on the detection result of the marking-related light.
The optical sorter according to any one of claims 1 to 3.
The light source is
A first light source located on the first side of the transfer path of the object to be sorted,
It comprises a second light source located on the second side opposite to the first side.
The optical sensor includes at least one of a first optical sensor arranged on the first side and a second optical sensor arranged on the second side.
The intermediate member is an optical sorter that has light non-transparency and substantially prevents light from passing through the intermediate member from the transfer path side and reaching the optical sensor.
The optical sorter according to any one of claims 1 to 4.
The marking is
At least one first unit region having a first color and a certain size, and at least one first having a second color different from the first color and having a certain size. Including at least 2 unit areas,
An optical sorter in which the first unit area and the second unit area are arranged one-dimensionally or two-dimensionally with a predetermined appearance pattern.
It ’s an optical sorter,
A light source configured to illuminate the object being transferred on the transfer path, and
A first optical sensor radiated from the light source and configured to detect light associated with the object to be sorted.
A determination unit configured to determine a foreign object and / or a defective product for the object to be sorted based on a signal acquired by the optical sensor with respect to the light associated with the object to be sorted.
It is arranged at a position between the light source and the transfer path in the direction of irradiation of the light from the light source to the object to be sorted, and at a position that does not affect the detection of the light associated with the object to be sorted. Intermediate members with markings and
An optical sorter comprising a second optical sensor configured to detect marking-related light emitted from the light source and obtained through the marking.
It ’s an optical sorter,
A light source configured to illuminate the object being transferred on the transfer path, and
An optical sensor configured to detect light emitted from the light source and associated with the object to be sorted.
A determination unit configured to determine the quality of the object to be sorted based on the signal acquired by the optical sensor with respect to the light associated with the object to be sorted.
It is arranged at a position between the light source and the transfer path in the direction of irradiation of the light from the light source to the object to be sorted, and at a position that does not affect the detection of the light associated with the object to be sorted. Equipped with an intermediate member with markings,
The optical sensor is further configured to detect marking-related light emitted from the light source and obtained through the marking.
The marking comprises multiple areas
Each of the plurality of regions is an optical sorter configured to provide at least one or more functions for ensuring the determination performance of the determination unit based on the marking-related light.
The optical sorter according to claim 7.
The at least one function includes at least one of a light amount detection function of the light source, a position shift detection function of the optical sensor, a focus shift detection function of the optical sensor, and a white balance confirmation function of the optical sensor. Optical sorter.