JP2023017898A - Optical-based screening machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve screening accuracy of an optical-based screening machine.

SOLUTION: An optical-based screening machine comprises: a light source that is configured to irradiate a screened object on the move on a transportation path with light; an optical sensor that is configured to detect the light radiated from the light source, and associated with the screened object; a determination unit that is configured to make a determination of a foreign object and/or a non-accepted object about the screened object on the basis of a signal to be acquired by the optical sensor of the light associated with the screened object; and an intermediate member that is arranged in a position which stands between the light source in an irradiation direction of the light to the screened object from the light source and the transportation path, and does not affect the detection of the light associated with the screened object, and has a marking. The optical sensor is configured to further detect marking-related light radiated from the light source, and to be obtained via the marking.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2023,JPO&INPIT

Description

The present disclosure relates to optical sorters.

2. Description of the Related Art Conventionally, an optical sorting machine has been known that uses optical information obtained by an optical sensor when an object to be sorted is irradiated with light from a light source to discriminate and remove foreign matter and defective products contained in the object to be sorted. (For example, Patent Document 1 below). The optical information (for example, color gradation value) obtained by the optical sensor is compared with a threshold value, and based on the comparison result, it is determined whether the item to be sorted is a non-defective item, a foreign material, or a defective item. be. Objects to be sorted that are determined to be foreign matter or defective products are typically blown away by an air jet, whereby the objects to be sorted are sorted into good products, foreign objects and defective products.

JP-A-61-212734

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

The present disclosure has been made to solve the above-described problems, and can be implemented, for example, as the following modes.

According to a first aspect of the present disclosure, an optical sorter is provided. The optical sorter comprises a light source configured to illuminate an item to be sorted as it is being transported on a transport path, and configured to detect light emitted from the light source and associated with the item to be sorted. an optical sensor configured to make a foreign and/or defective determination of an item to be sorted based on a signal obtained by the optical sensor for light associated with the item to be sorted; and a light source. an intermediate member having a marking, positioned between the light source and the transport path in the direction of illumination of the light from to the items to be sorted, such that it does not affect the detection of the light associated with the items to be sorted; I have. The optical sensor is further configured to detect marking-related light emitted from the light source and obtained through the marking.

The “light associated with the object to be sorted” may be reflected light that is light reflected by the object to be sorted, transmitted light that is light that has passed through the object to be sorted, or , both reflected light and transmitted light.

According to this optical sorting machine, it is possible to perform various processes for improving the sorting accuracy based on the marking-related light detected by the optical sensor. For example, it is possible to detect the amount of light from the light source based on the marking-related light and determine whether the amount of light is within an appropriate range. Further, the intermediate member is positioned so that the optical sensor does not affect the detection of light associated with the items to be sorted so that marking-related light can be detected during the sorting operation of the optical sorter. Moreover, since the optical sensor can be used both for detecting the light associated with the objects to be sorted and for detecting the marking-related light, there is no need to provide an additional optical sensor only for the detection of the marking-related light.

According to a second aspect of the present disclosure, in the first aspect, the optical sorting machine includes a detection unit configured to detect the state of the optical sensor based on the detection result of the marking-related light. . According to this aspect, it is possible to perform various processes for suppressing deterioration of sorting accuracy caused by the state of the optical sensor, based on the detected state of the optical sensor. For example, by notifying an abnormality related to the state of the optical sensor, it is possible to prevent the optical sorter from being operated 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 detected, the detected state of the optical sensor can be used as information for clarifying the cause of the deterioration. The detected optical sensor condition may include, for example, a condition associated with the installation position of the optical sensor.

According to the third aspect of the present disclosure, in the second aspect, the state of the optical sensor detected by the detection unit includes the presence or absence of misalignment of the optical sensor, the amount of misalignment, the direction of misalignment, and the optical sensor. It includes at least one of presence/absence of defocus of the sensor. According to this aspect, it is possible to perform various kinds of processing for suppressing deterioration of sorting accuracy due to misalignment or defocus of the optical sensor.

When the state of the optical sensor detected by the detection unit includes the amount and direction of positional deviation, it is easy to implement processing or measures for suppressing deterioration in sorting accuracy due to positional deviation. 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 adjustment work to eliminate the positional deviation.

If the state of the optical sensor detected by the detection unit includes the presence or absence of defocus of the optical sensor (that is, a state in which the object to be sorted cannot be focused), deterioration of the sorting accuracy due to defocus is prevented. Various treatments can be implemented to suppress. For example, the optical sorting machine may notify the user when defocus is detected.

The optical sorting machine ejects air toward a specific object to be sorted determined based on the determination result of the judging unit to deviate the specific object to be sorted from the transfer route, thereby removing foreign matter and/or defective products. A sorting unit for sorting may be provided. When the transport path extends in the first direction and the objects to be sorted are transported in the first direction with a predetermined width in a second direction orthogonal to the first direction, the sorting unit moves in the second direction. appropriate position toward a specific object to be sorted based on a predetermined correspondence relationship between the position where the light associated with the object to be sorted is detected in the second direction and the position where the air is to be injected in the second direction may be configured to inject air from In this case, the optical sorting machine may further include a first correction unit that corrects the predetermined correspondence based on the amount of positional deviation of the optical sensor in the second direction.

Furthermore, the sorting unit may be configured to inject air at a timing determined based on a predetermined delayed injection time. Delayed injection time is the time from detection of light associated with a particular object to injection of air. In this case, the optical sorting machine may include a second correction unit that corrects the predetermined delayed injection time based on the amount of positional deviation 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 aspects, the optical sorting machine detects the light associated with the object to be sorted based on the detection result of the marking-related light. a color corrector configured to perform color correction on the According to this aspect, it is possible to adjust the color tone of the image represented by the detection result of the optical sensor. 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 markings are color markings, non-linear color correction may be performed.

According to a fifth aspect of the present disclosure, in any one of the first to fourth aspects, the optical sorting machine includes a calibration unit configured to be able to perform calibration based on the detection result of the marking-related light It has According to this aspect, fluctuations in the light intensity of the light source can be satisfactorily compensated 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 light amount of the light source based on the detection result of the marking-related light. According to this form, fluctuations in the amount of light from the light source can be compensated for without amplifying noise.

According to a seventh aspect of the present disclosure, in the fifth or sixth aspect, the calibration includes adjusting the gain for the signal acquired by the optical sensor based on the detection result of the marking-related light. According to this aspect, fluctuations in the amount of light emitted from the light source can be compensated regardless of the ability of the light source to adjust the amount of light emitted.

According to the eighth aspect of the present disclosure, in any one of the first to seventh aspects, the light sources include a first light source arranged on the first side with respect to the transport path of the objects to be sorted; a second light source positioned on a second side opposite the side. The optical sensor comprises at least one of a first optical sensor located on the first side and a second optical sensor located on the second side. The intermediate member is light impermeable and substantially prevents light from reaching the optical sensor through the intermediate member from the transport path side. According to this aspect, 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 emitted from the intermediate member. It cannot pass through the member to 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 It is not detected by the first optical sensor. Similarly, when the optical sensor comprises a second optical sensor, the intermediate member is arranged on the second side, and light emitted from the first light source located on the first side is transmitted through the intermediate member. to reach the second optical sensor located on the second side. Therefore, when detecting the light amount of the light source based on the marking-related light, the light amount can be detected more accurately. Further, by combining the eighth mode with the second mode, the state of the optical sensor can be detected more accurately. Moreover, when combined with the fifth mode, calibration with higher accuracy can be performed based on the light amount of the light source that is accurately detected. Furthermore, if the optical sensor includes both the first optical sensor and the second optical sensor, the light intensity of the first light source and the light intensity 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 aspects, the marking includes at least one first unit region having a first color and a certain size; and at least one second unit area having a second color different from the first 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 area is an area having a predetermined size and shape.

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

When the transport path extends in the first direction and the objects to be sorted are transported in the first direction with a predetermined width in the second direction perpendicular to the first direction, the first unit area and the second unit area 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 regions and the second unit regions in the second direction are different for each alignment position of the first unit regions and the second unit regions in the first direction. good. With this configuration, it is possible to easily detect the amount of positional deviation and the direction of positional deviation 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. In other words, a marking is a mark created based on a predetermined system in order to represent some kind of information. According to this aspect, when the tenth aspect is combined with the second aspect, the state of the optical sensor (for example, presence or absence of misalignment, presence or absence of focus misalignment) is determined based on whether or not the information represented by the code can be read. can be easily detected. Furthermore, if the marking is a two-dimensional code, the amount of positional deviation can be detected based on what kind of information is read.

According to an eleventh aspect of the present disclosure, an optical sorter is provided. This optical sorter replaces the optical sensor of the first form with a first optical sensor illuminated from the light source and configured to detect light associated with the items to be sorted; , and a second optical sensor configured to detect marking-related light obtained through the marking. This form also provides the same effects as the first form. It is also possible to combine any of the second to tenth forms with the eleventh form. When the second mode is combined with the eleventh mode, the detector is configured to detect the state of the second optical sensor.

According to a twelfth aspect of the present disclosure, an optical sorter is provided. This optical sorter
a light source configured to illuminate an item to be sorted as it is being transported over a transfer path; an optical sensor configured to detect light emitted from the light source and associated with the item to be sorted; a determination unit configured to determine the quality of an object to be sorted based on a signal acquired by an optical sensor regarding light associated with the object; and an intermediate member having markings positioned between and the transport path at a location that does not affect the detection of light associated with the items to be sorted. 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 configured to provide at least one or more functions for ensuring determination performance of the determination unit based on marking-related light. According to this optical sorting machine, it is possible to perform various kinds of processing for improving the determination performance of the determination section, and thus the sorting accuracy, by using each of the plurality of regions.

According to the thirteenth form of the present disclosure, in the twelfth form, the at least one function is the light amount detection function of the light source, the positional deviation detection function of the optical sensor, the focus deviation detection function of the optical sensor, and the optical sensor At least one of white balance confirmation functions is included.

According to a fourteenth aspect of the present disclosure, in the thirteenth aspect, the optical sensor includes a plurality of linearly arranged light receiving elements. Such optical sensors may be line sensors or area sensors. At least a portion of the plurality of regions includes a first region configured to provide misalignment detection functionality for the optical sensor. The first region comprises small regions that are identifiable by color differences. The width of the small area in the array direction of the plurality of optical elements is uniquely set according to the position in the direction intersecting the array direction. The "direction intersecting with the arrangement direction" may be a direction perpendicular to the arrangement direction. According to this aspect, it is possible to easily detect the positional deviation of the optical sensor based on the marking-related light. Specifically, when the optical sensors are displaced in a direction intersecting the arrangement direction, the direction and amount of displacement can be grasped based on the width of the small area detected by the optical sensors. Also, when the optical sensors are displaced in the arrangement direction, the direction and amount of displacement can be grasped based on the positions of the start points and/or end points of the small areas detected by the optical sensors. The fourteenth mode can also be implemented independently of the twelfth mode. For example, as markings, only the above-mentioned small areas may be used alone.

According to a fifteenth form of the present disclosure, in the thirteenth or fourteenth form, at least a portion of the plurality of areas includes a second area configured to provide a defocus detection function. The second area comprises small areas that are identifiable by color differences. According to this aspect, it is possible to easily detect the defocus of the optical sensor. For example, the defocus of the optical sensor may be detected based on the state of edge detection representing the boundary of the small area in the marking-related light image data corresponding to the second area. In this case, if a sharp edge of a predetermined degree is detected, it may be determined that defocus has not occurred, and if the sharp edge is not detected, defocus has occurred. may be determined. Alternatively, the defocus of the optical sensor may be detected based on the detection status of the small area in the marking-related light image data corresponding to the second area. In this case, for example, a small area having a small size (e.g., width) is set, and when the small area is detected, it may be determined that the focus shift has not occurred, and the small area is detected. If not, it may be determined that a focus shift has occurred. Also, 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 that is thinner than the first line. In this case, the first line and the second line can detect the first line with the optical sensor but not the second line when the optical sensor is focused on the detection position of the object to be sorted. If not, the thickness may be set such that the optical sensor can detect both the first line and the second line when the optical sensor is focused on the position of the marking. The fifteenth mode can also be implemented independently of the twelfth mode. For example, only the second area may be used alone as a marking.

According to one aspect of the present disclosure, the optical sensor is a line sensor or area sensor having a plurality of linearly arranged light receiving elements. The intermediate member is arranged at a position that does not overlap 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 light associated with the items being sorted during transfer but not marking related light and light receiving elements not detecting light associated with the items being sorted during transfer but not marking related. and a light receiving element that detects light.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows schematic structure of the optical sorting machine by 1st Embodiment. It is a schematic diagram which shows the positional relationship of a light source, an intermediate member, and an optical sensor. It is a sectional view of an intermediate member. It is a figure which shows an example of the marking which an intermediate member has. FIG. 11 illustrates marking according to the second embodiment; FIG. 10 is a chart showing examples of various markings; FIG.

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 this embodiment, the sorting machine 10 sorts rice grains (more specifically, brown rice or polished rice) as the object 90 to be sorted into foreign objects (eg, pebbles, mud, glass fragments, etc.) and defective products (eg, immature grains). , colored grains, etc.). However, the object 90 to be sorted is not limited to brown rice or polished rice, and may be any granular object. For example, the object 90 to be sorted may be rice, wheat grains, beans (soybeans, chickpeas, green soybeans, etc.), resins (pellets, etc.), rubber pieces, and 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. 80 and . Controller 80 controls the overall operation of sorter 10 . The controller 80 also functions as a determination section 81 , a detection section 82 , a first correction section 83 , a second correction section 84 , a color correction section 85 and a calibration section 86 . The functions 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 controller 80 may be distributed over at least two devices. Details of the functions of the controller 80 will be described later.

The storage tank 71 temporarily stores the objects 90 to be sorted. The feeder 72 supplies the objects 90 to be sorted stored in the storage tank 71 onto a chute 73 as an example of means for transferring objects to be sorted. The objects to be sorted 90 supplied onto the chute 73 slide downward on the chute 73 and drop from the lower end of the chute 73 . The chute 73 has a predetermined width capable of simultaneously dropping a large number of objects 90 to be sorted. In the following description, the direction in which the transfer path 95 of the objects 90 to be sorted after dropping from the chute 73 (in other words, the drop trajectory of the objects 90 to be sorted) extends is also called the first direction D1. The width direction of the chute 73 (in other words, the direction perpendicular to the direction in which the objects 90 to be sorted fall on the bottom surface of the chute 73) is also called a second direction D2. The second direction D2 is orthogonal to the first direction D1.

The optical detection unit 20 irradiates light onto the objects 90 to be sorted that have slid down from the chute 73, and emits light associated with the objects 90 to be sorted (specifically, transmitted light transmitted through the objects 90 to be sorted, and , reflected light reflected by the object 90 to be sorted). An output from the optical detection unit 20, that is, an analog signal representing the intensity of the detected light is amplified with a predetermined gain by an AC/DC converter (not shown) and 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 . The controller 80 determines whether the object 90 to be sorted is a non-defective product (that is, relatively high-quality rice grains) or foreign matter, as the processing of the determination unit 81 based on the input light detection result (that is, image). (that is, non-rice grains) or defective (that is, rice grains of relatively low quality). This determination is made for each of the objects 90 to be sorted. 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.

Objects 90 to be sorted that are determined to be foreign matter or defective are sorted by the sorting unit 76 . Specifically, the sorting unit 76 includes an ejector 77 that ejects air 78 toward the objects 90 to be sorted. Objects 90 to be sorted that are determined to be foreign matter or defective products are blown away by air 78, deviate from the trajectory of falling from chute 73 (that is, transfer path 95), and are guided to defective product discharge gutter 75 (see FIG. 1). (shown as an object 91 to be sorted). On the other hand, the air 78 is not injected to the objects 90 to be sorted that are determined to be non-defective products. For this reason, the objects 90 to be sorted that have been determined to be non-defective products are guided to the non-defective product discharge trough 74 (shown as the objects to be sorted 92 in FIG. 1) without changing the falling trajectory.

Details of the functions of the optical detection unit 20 and the controller 80 will be described below. As shown in FIG. 1, the optical detection section 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 transport path 95 of the objects 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 transport path 95 of the objects 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 objects 90 to be sorted that are being transported on the transport path 95 (that is, that are falling from the chute 73) with the light 31a. Similarly, the second light source 30b irradiates the objects 90 to be sorted during transportation 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, an LED is used as the light emitting element 32a. Therefore, the light emitting element 32a is also called an LED 32a. The plurality of LEDs 32a includes 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.

Although the number of each of the first light source 30a and the second light source 30b is one in FIG. 1, at least one of the first light source 30a and the second light source 30b may be plural. There may be. For example, two first light sources 30a may be arranged above and below the detection position on the transfer path 95, respectively. Similarly, two second light sources 30b may be positioned above and below the detection position on the transfer path 95, respectively.

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

The first optical sensor 40a is a line sensor having a plurality of linearly arranged light receiving elements 41a in this embodiment. However, the first optical sensor 40a may be an area sensor. The multiple 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 90 to be sorted that are transported over a predetermined width of the chute 73. As shown in FIG. Also, the first optical sensor 40a is a color CCD sensor in this embodiment, and is capable of individually detecting red light, green light, and blue light. However, the first optical sensor 40a may be other types of sensors such as a color CMOS sensor. In this 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.

The optical detection section 20 further includes transparent members 21a and 21b. The transparent member 21a separates the first light source 30a and the first optical sensor 40a from the transport path 95 on the front side. As a result, the first light source 30a and the first optical sensor 40a are separated from the transport path 95, and dust scattered from the transport path 95 adheres to the first light source 30a and the first optical sensor 40a. is prevented. Similarly, the transparent member 21b separates the second light source 30b and the second optical sensor 40b from the transport path 95 on the rear side.

The optical detection unit 20 further includes intermediate members 50 on the front side and the rear side. 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 objects 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 objects 90 to be sorted.

FIG. 2 is a schematic diagram showing the positional relationship in the second direction D2 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. is. Since the illustrated positional relationship is the same for 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 in the second direction D2 of the first optical sensor 40a. Further, "V2" shown in FIG. 2 indicates the field of view of raw material, that is, the range in which the object 90 to be sorted can be imaged. The width of the raw material visual field V2 corresponds to the width of the chute 73 (in other words, the width of the transport path 95). The plurality of light receiving elements 41a are arranged so as to extend outside the raw material visual field V2 in the second direction D2. As a result, the non-raw material visual field V3 of the first optical sensor 40a is secured on both sides of the raw material visual field V2 in the second direction D2.

The intermediate member 50 is arranged in a region of the transparent member 21a corresponding to the non-raw material visual field V3. In other words, the intermediate member 50 is arranged at a position that does not affect the detection of the light associated with the object 90 to be sorted by the first optical sensor 40a. This position is, in other words, a position that does not overlap the transfer path 95 when viewed in any direction orthogonal to the second direction D2. In this embodiment, the intermediate members 50 are 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 visual field V3). The intermediate member 50 is located outside the boundary between the raw material visual field V2 and the non-raw material visual field V3 in the second direction D2. 41a will not be detected. Conversely, the light associated with the item 90 to be sorted is not detected by the light receiving element 41a corresponding to the non-raw material field V3. Similarly, the rear-side intermediate member 50 reflects the light 31b emitted from the rear-side second light source 30b. 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 visual field V3).

As is clear from this description, the first optical sensor 40a is used both to detect the light associated with the object 90 to be sorted and to detect the light 31a reflected by the intermediate member 50. FIG. Similarly, the second optical sensor 40b is shared for detecting light associated with the items 90 to be sorted and for detecting light 31b reflected by the intermediate member 50. FIG.

In this embodiment, the intermediate member 50 is in the form of a sheet 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 sorting machine 10 can be simplified. Moreover, 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. As shown in FIG. FIG. 3 shows the rear-side intermediate member 50 attached to the transparent member 21b. As illustrated, the rear-side intermediate member 50 has a two-layer structure. Specifically, the intermediate member 50 includes a first layer 51 located on the transport path 95 side and a second layer 52 located on the opposite side of the transport path 95 . The first layer 51 is light impermeable. 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 Although illustration is omitted, similarly, the front-side intermediate member 50 attached to the transparent member 21a also includes the first layer 51 positioned on the transport path 95 side and having light impermeability, and the first layer 51 opposite to the transport path 95. and a flanking second layer 52 . 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

The second layer 52 is at least partially formed from a material that is light reflective. 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 reflects the light emitted from the second light source 30b. reflected light 31b.

In this 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. For this reason, the intermediate member 50 is not affected by dust generated as the objects 90 to be sorted are transferred. Moreover, the exposed surface of the first layer 51 (that is, the surface opposite to the second layer 52) serves as the adhesive surface of the intermediate member 50 with the transparent members 21a and 21b, and the exposed surface of the second layer 52 (that is, , the reflective surface that reflects the light 31b) does not have adhesive. Therefore, there is no risk that the adhesive will hinder the reflection performance of the second layer 52 . However, the intermediate member 50 may be arranged on the transport 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 it is not affected by dust.

The intermediate member 50 (more specifically, the second layer 52) has markings 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 (in other words, reflected light from the marking 53). Such light obtained via marking 53 is also referred to as marking-related light. The markings 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. As shown in FIG. FIG. 4 shows the marking 53 viewed in a direction perpendicular 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 areas UA. The unit area UA has a predetermined constant 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 square in the example shown in FIG. 4, but may be of any shape. The marking 53 includes a first unit area 54 having a first color and a second unit area 55 having a second color. In this embodiment, the first color is black and the second color is white. The first unit area 54 and the second unit area 55 are arranged two-dimensionally 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 same as that of the first unit region 54 and the second unit region 55 in the first direction D1. 2 unit regions 55 are arranged in different positions (indicated as positions P1 to P19 in FIG. 4).

According to the sorting machine 10 described above, it is possible to use the marking-related light to perform various processes for improving the sorting accuracy. Such processing will be described below. 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 the processing 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 rear-side second optical sensor 40b is detected based on marking-related light obtained through the marking 53 of the intermediate member 50 attached to the rear-side transparent member 21b.

The states of the first optical sensor 40a and the second optical sensor 40b detected by the detection unit 82 include states related to the installation positions of the first optical sensor 40a and the second optical sensor 40b. Such states related to the installation position include the presence or absence of positional deviation, the amount of positional deviation, the direction of positional deviation, and the presence or absence of focus deviation of the first optical sensor 40a and the second optical sensor 40b. At least one may be included.

The presence or absence of misalignment and 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 first optical sensor 40a picks up an image of the area on the line L1. In this case, when the appearance pattern detected based on the marking-related light is the appearance pattern of the alignment position P10, the first optical sensor 40a can detect that there is no deviation in the first direction D1. On the other hand, when the appearing pattern detected based on the marking-related light is the appearing pattern at the alignment position P12, the first optical sensor 40a moves in the first direction D1 (more specifically, from the alignment position P1). It can be seen that there is a shift to the position of line L2 in the direction toward position P19. The amount of deviation at this time is about two times the size of the unit area UA (more precisely, a distance larger than the length of one side of the unit area UA and smaller than twice the length). detected.

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

The appearance pattern of each of the alignment positions P1 to P19 may be stored in the memory of the controller 80 when the sorting machine 10 is manufactured. In addition, detection from 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 installed in place during the manufacturing stage of the sorting machine 10 The resulting pattern of appearance may be stored in the memory of the controller 80 as the pattern of appearance corresponding to the first optical sensor 40a and the second optical sensor 40b in the normal position. Similarly, the position of the light receiving element that 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 in the normal position. .

Further, the presence or absence of defocus can be detected, for example, as follows. In one embodiment, the marking-related light image data (RAW data) is first binarized. In this binarization, pixel values corresponding to gray caused by defocus are converted into pixel values corresponding to white. Then, by pattern matching, it is determined whether or not the appearance pattern represented by the binarized image matches any of a plurality of pre-stored appearance patterns (that is, the appearance patterns of the alignment positions P1 to P19). be done. If the appearance pattern represented by the image obtained by binarization does not match any of the pre-stored appearance patterns, it can be detected that the defocus has occurred. In an alternative embodiment, defocus may be detected based on whether a predetermined degree of sharp edge is detected in the marking-related light image data.

In the present embodiment, the intermediate member 50 is arranged on both sides of the transfer path 95 in the second direction D2, so that the first optical sensor 40a or the second optical sensor 40b can be positioned in the second direction D2. Even if one side is slightly misaligned to the extent that it does not affect the sorting accuracy, and the other side is misaligned to the extent that it affects the sorting accuracy, the misalignment can be prevented. can be reliably detected.

When the detection unit 82 detects the positional deviation or the focus deviation of the first optical sensor 40a or the second optical sensor 40b, the controller 80 notifies the user of the detected content via the notification unit 88. good. The notification unit 88 may be in the form of a screen on the operation panel of the sorting machine 10, a speaker, a light, or the like. In other words, the notification can be in the form of a display on the screen, a warning sound, lighting of lights, or the like. According to this configuration, the user can quickly notice an abnormality in the position or focus state of the first optical sensor 40a or the second optical sensor 40b and perform work to eliminate the abnormality. As a result, the sorting operation of the sorter 10 is continued despite the occurrence of an abnormality, and deterioration of the sorting accuracy is suppressed. Furthermore, when the controller 80 is configured to notify the direction and amount of positional deviation, the user can use the first optical sensor 40a or the second optical sensor 40a when performing adjustment work to eliminate the positional deviation. It is easy to grasp in which direction and how much the installation position of the optical sensor 40b should be moved. If the first optical sensor 40a and the second optical sensor 40b have an autofocus function, the focus deviation may be automatically eliminated when the focus deviation is detected.

In the present embodiment, when the positional deviation of the first optical sensor 40a or the second optical sensor 40b is detected, the controller 80 further performs processing for suppressing the deterioration of the sorting accuracy caused by the positional deviation. can be done automatically. This process is executed as a process of at least one of the first corrector 83 and the second corrector 84 .

First, processing of the first correction unit 83 will be described. In the sorting section 76, a plurality of valves (not shown) for controlling injection of air 78 are arranged in the second direction D2 in order to simultaneously sort out the plurality of objects 90 to be sorted which are simultaneously transferred across the width of the chute 73. It is One of the valves is assigned to each detection position 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 in the second direction D2 where the light associated with the object 90 to be sorted is detected (hereinafter also referred to as the detection position) and the position in the second direction D2 where the air 78 is to be injected (hereinafter also referred to as the detection position). , is also called an injection position) is determined in advance. When one object 90 to be sorted is determined to be a foreign object or a defective product, the air 78 is jetted from the injection position corresponding to the detected position of the one object 90 to be sorted.

As the processing of the first correction unit 83, the controller 80 adjusts the correspondence between the detection position and the injection position based on the amount of positional deviation of the first optical sensor 40a or the second optical sensor 40b in the second direction D2. 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 detected position in the corresponding relationship between the detected position and the injection position is shifted to the corresponding position. It is shifted in the direction of positional shift by the amount of shift. Therefore, correction is performed by shifting the injection position corresponding to the detected position by the amount of the positional deviation in the direction opposite to the direction of the positional deviation. As a result, the correspondence relationship returns to its 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 shifted in the second direction D2, the sorting accuracy is not deteriorated due to the positional deviation. can be automatically suppressed.

Next, processing of the second correction unit 84 will be described. In the first direction D1, the position where the trajectory of the object 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, after the first optical sensor 40a or the second optical sensor 40b detects the foreign matter or the defective product, the sorting unit 76 airs the foreign matter or the defective product at a timing delayed by a predetermined time. 78. This time difference is also commonly referred to as a 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 90 to be sorted, the actually measured falling speed of the object 90 to be sorted, etc.). It may be determined in advance.

The controller 80 corrects the delayed injection time as processing of the second correction unit 84 based on the amount of positional deviation 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 its normal position, the first The distance between the detection position of the object 90 to be sorted by the optical sensor 40a or the second optical sensor 40b and the track change position is reduced. Therefore, the controller 80 shortens the delayed injection time according to the deviation amount in the first direction D1. Conversely, if the first optical sensor 40a or the second optical sensor 40b is displaced upward in the first direction D1 from its normal position, the controller 80 determines the amount of displacement in the first direction D1. Extend the delayed injection time accordingly.

The delayed injection time may be corrected using a function with the amount of positional deviation of the first optical sensor 40a or the second optical sensor 40b in the first direction D1 as a variable. This function may be predetermined by experimentation and stored in the memory of controller 80 . Alternatively, the distance between the normally detected 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 inclination angle of the chute 73, the transfer speed of the object 90 to be sorted (this is may be actually measured or predetermined by experiment), based on the amount of displacement of the first optical sensor 40a or the second optical sensor 40b in the first direction D1, etc. may be calculated by simple calculation. 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 misalignment causes the sorting accuracy to deteriorate. can be automatically suppressed.

In this embodiment, the amount of positional deviation is detected on both sides of the transfer path 95 in the second direction D2. Therefore, when the detected amount on one side and the detected amount on the other side are different, for example, the average value of the detected amounts on both sides is used to perform the processing of the first correction unit 83 and the second correction unit 84. 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 performed as an initial adjustment when the sorting machine 10 is manufactured or initially used. Alternatively, these processes may be performed at predetermined timings when the sorter 10 is in use (that is, during sorting operation). The installation positions of the first optical sensor 40a and the second optical sensor 40b may shift due to impact received during transportation of the sorting machine 10. Positional deviation can also be suitably dealt with. Further, the processing of the first correcting unit 83 and the second correcting unit 84 may be automatically executed when positional deviation is detected, or may be executed manually, or It may be executed when no user operation is performed for a predetermined period of time after notification of the occurrence of positional deviation.

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

Furthermore, the controller 80 can perform white balance correction based on the imaging result of the white second unit area 55 . For example, when an image is expressed in 256 gradations, the representative value of the color gradation values of the image data of the first unit area 54 corresponds to the gradation value 0, and the image data of the second unit area 55 corresponds to the gradation value 0. A linear white balance correction may be performed so that the representative value of the color gradation values of corresponds to the gradation value 255. Such color correction processing may be performed, for example, when the sorting machine 10 starts sorting operation. 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 can be brought close to that before the replacement. can be done. This point is particularly effective when the model number of the part to be replaced has been discontinued and a new replacement part is to be installed.

Furthermore, according to the sorting machine 10 described above, the light amounts of the first light source 30a and the second light source 30b are detected based on the marking-related light (more specifically, the imaging result of the second unit area 55). can. Intermediate member 50 having markings 53 is located in a position that does not affect the detection of light associated with items 90 to be sorted so that during sorting operation of sorter 10 the first light source 30a and second light source 30b The amount of light can be detected in real time. Moreover, no additional optical sensor is required to detect the light intensities of the first light source 30a and the second light source 30b.

The first layer 51 of the intermediate member 50 has light impermeability as described above. 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 detected together 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 light amount 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 from 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 only one of the first light source 30a and the second light source 30b fluctuates in light intensity, the light intensity of the first light source 30a and the light intensity of the second light source 30b can be accurately separately determined. can be detected. The light impermeability of the first layer 51 also allows for more accurate detection of the shape of the marking 53 and, in turn, more accurate detection of the states of the first optical sensor 40a and the second optical sensor 40b. To contribute.

According to the sorting machine 10, it is possible to detect the light amounts of the first light source 30a and the second light source 30b 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 compared to the case where the light amount is detected only on one side. For example, when a light amount abnormality occurs only on one side in the second direction D2, it is easy to grasp the abnormality.

In the present embodiment, the sorting machine 10 further performs calibration and Notification can be made. The configuration will be described below. In this embodiment, the calibration is repeatedly performed during the sorting operation of the sorter 10 as processing of the calibration section 86 of the controller 80 . Specifically, the calibration unit 86 first obtains the light amounts of the first light source 30a and the second light source 30b obtained using the marking-related light as described above. This amount of light is obtained for each RGB color component. In addition, this amount of light is acquired for each of the one side and the other side in the second direction D2. The amount of light to be acquired is the statistical value (for example, average value, median 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 TH1 and the second threshold TH2, and the reference value representing the ideal amount of light is included in this first range. For example, the first threshold TH1 may be set as a value minus 30% with respect to the reference value, and the second threshold TH2 may be set as a value plus 30% with respect to the reference value.

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

On the other hand, if the light intensities for all of the RGB color components are within the first range, then the calibration section 86 determines whether the acquired light intensities are within the second range. The second range may be preset for each RGB color component. This second range is the range bounded by a third threshold TH3 (TH1<TH3) and a fourth threshold TH4 (TH4<TH2), and the reference value is contained within this second range. Then, as a result of determination, if the acquired light amount is not within the second range, the calibration unit 86 performs calibration. Calibration here is processing for adjusting the light intensity of the first light source 30a and the second light source 30b according to the detected light intensity. Specifically, the calibration unit 86 adjusts the light amounts 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. In addition, in the present embodiment, the light amount is detected on both sides of the transport path 95 in the second direction D2. Similarly, based on the light intensity detection result on the other side in the second direction D2, the light intensity of the light emitting elements 32a and 32b positioned on the other side is adjusted. If calibration is performed by adjusting the amount of light, fluctuations in the amount of light of the first light source 30a and the second light source 30b can be compensated for without amplifying noise.

In this embodiment, the controller 80 adjusts the light intensity of the light emitting elements 32a and 32b by PWM control. More specifically, when the sorting machine 10 is shipped, the controller 80 is set to apply a voltage to the light emitting elements 32a and 32b with a duty ratio of 50%. Then, the calibration section 86 compensates for fluctuations in the amount of light emitted from the light emitting elements 32a and 32b by increasing or decreasing the duty ratio. That is, when the light intensity of the light emitting elements 32a and 32b is greater than the reference value, the calibration unit 86 reduces the duty ratio so that the light intensity becomes the reference value, and the light intensity of the light emitting elements 32a and 32b is less than the reference value. Sometimes, the duty ratio is increased so that the amount of light becomes the 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 greater than the reference value and when it is less than the reference value. Note that when the amount of light does not reach the reference value even if the duty ratio is changed, the controller 80 notifies via the notifying section 88 .

On the other hand, if the acquired amount of light is within the second range, the calibration unit 86 determines not to perform calibration. In other words, if the variation in the amount of light is small enough to eliminate the need for calibration, execution of 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 in real time. Moreover, the above-described intermediate member 50 can accurately detect the respective light amounts of the first light source 30a and the second light source 30b separately, so that the accuracy of calibration 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 fall within the same reference range. Therefore, the accuracy of determination by the determination unit 81 is improved.

Furthermore, according to the calibration unit 86, if the degree of light intensity fluctuation of the first light source 30a and the second light source 30b is such that the determination accuracy can be appropriately secured by the calibration, the calibration is executed and the determination is performed. 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 light amount fluctuation.

In an alternative embodiment, the calibration unit 86 performs calibration if the amount of light detected is within the first range. In other words, 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 if the difference is very small. According to this form, it is possible to more strictly compensate for variations in the amount of light from the first light source 30a and the first optical sensor 40a.

In a further alternative embodiment, the calibration unit 86 adjusts the gain of the signals acquired by the light receiving elements 41a and 41b corresponding to the raw material visual field V2 instead of adjusting the light amounts of the light emitting elements 32a and 32b. to perform the calibration. That is, when the light intensity of the light emitting elements 32a and 32b is greater than the reference value, the calibration unit 86 reduces the gain by the ratio, and when the light intensity of the light emitting elements 32a and 32b is less than the reference value, the gain is reduced by the ratio. increase the gain by In this embodiment, the gain is changed by changing the gain in the AC/DC converter. A gain of the amplifier circuit may be changed. According to this form, fluctuations in the light intensity of the first light source 30a and the second light source 30b can be compensated regardless of the light intensity adjustment capability 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 the mode of adjusting the light intensity of the light emitting elements 32a and 32b and the mode of adjusting the gain. For example, the default duty ratio may be set to 100%. In this case, when the light intensity of the light emitting elements 32a and 32b is greater than the reference value, the calibration unit 86 reduces the duty ratio so that the light intensity becomes the reference value, and the light intensity of the light emitting elements 32a and 32b becomes higher than the reference value. When it is small, the gain is increased by that ratio. According to this form, when the light intensity of the light emitting elements 32a and 32b is within an appropriate range, the light intensity can be sufficiently secured. Alternatively, if the default duty ratio is set to less than 100% (for example, 90%) and the light intensity does not reach the reference value even after the duty ratio is increased to 100%, the gain is adjusted for the insufficient light intensity. may be performed.

The calibration processing and notification processing described above can be performed at arbitrary timing. For example, these processes may be performed before the operation of the sorter 10 is started instead of during the sorting operation of the sorter 10 or in addition. Furthermore, when the sorting machine 10 is configured to be able to clean the transparent members 21a and 21b with a wiper and is configured to temporarily interrupt the sorting process for cleaning, the calibration process and notification processing may be performed during the cleaning.

In the sorting machine 10 described above, the size of the unit area UA of the marking 53 may be set to the same extent as the size of the field of view of each of the plurality of light receiving elements 41a and 41b. In this way, positional deviations of the first optical sensor 40a and the second optical sensor 40b can be detected with high accuracy. Alternatively, the size of the unit area UA may be set to about half the minimum dimension of the object 90 to be sorted (for example, grain thickness for rice) (for example, about 1.5 mm for rice). . In this way, it is possible to detect only positional deviations that greatly affect the sorting accuracy. Alternatively, the size of the unit area UA may be set to be equal to or larger than the size of the field of view of each of the plurality of light receiving elements 41a and 41b and approximately half or less of the minimum size of the object 90 to be sorted.

In alternate embodiments, various markings may be used in place of the markings 53 illustrated in FIG. For example, the marking may be any color other than white and black instead of or in addition to at least one of the black first unit area 54 and the white second unit area 55 shown in FIG. A unit area may be included. Other unit areas may include two or more types of unit areas having different colors. Additionally, the markings may be color markings having two or more colors other than white and black. For example, the marking may have unit areas of white, black, red, green, blue, cyan, magenta, and yellow, respectively. When such color markings are used, the color correction section 85 may be configured to perform non-linear color correction so that each gradation value of the image of the markings approaches a predetermined color. Furthermore, the unit areas of the same color or different colors may be spaced from each other, or may be adjacent to each other without a space, as in the example shown in FIG.

Furthermore, the unit areas do not necessarily have to be arranged two-dimensionally, and may be arranged one-dimensionally only in the second direction D2. This makes it possible to detect the amount of positional deviation in the second direction D2.

Furthermore, two-dimensional codes may be used as markings. Even in this way, effects similar to those of the above-described embodiment can be obtained. The two-dimensional code may be a known standardized code, such as a stack type (PDF417, CODE49, etc.) or a matrix type (QR Code (registered trademark), Data Matrix, VeriCode (registered trademark), etc.). There may be. Alternatively, the two-dimensional code may be independently developed.

Additionally, one-dimensional codes (eg, barcodes) may be used as markings. In this case, if the markings are arranged so that the bars are aligned in the second direction D2, it is possible to detect the amount of positional deviation in the second direction D2. When a one-dimensional or two-dimensional code is used as a marking, the state of the optical sensor (e.g. misalignment, defocus) can be easily detected based on whether the information represented by the code can be read. . Furthermore, if the marking is a two-dimensional code, the amount of positional deviation in the first direction D1 can be detected based on what kind of information was read.

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

A second embodiment will be described below. The second embodiment differs from the first embodiment only in that markings 153 are provided instead of the markings 53, and the device 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 comprises a first area 154, a second area 155 and a third area 156. As shown in FIG. Each of these areas 154 to 156 provides at least one or more functions for ensuring the determination performance of the determination section 81 based on marking-related light. In this embodiment, each of regions 154-156 serve different functions. The areas 154 to 156 will be specifically described below.

A first region 154 provides a misalignment detection function for the optical sensors 40a, 40b. This first area 154 comprises a small black area 157 . The small region 157 has a trapezoidal shape with upper and lower bases parallel to the second direction D2. A white left small region 158 and a white right small region 159 are located on both sides of the small region 157 in the second direction D2. In other words, the boundaries of the small regions 157 are identified by different colors. The width W1 of the small region 157 in the second direction D2 is uniquely determined according to the position in 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 the first area 154, it is possible to detect the presence, direction, and amount of positional deviation 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 in the first direction D1 and the upper linear area A2 is captured by the first optical sensor 40a, the small area detected by the first optical sensor 40a Width W1 of region 157 increases in proportion to the amount of deviation compared to 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 of the first direction D1 and the lower linear area A3 is imaged by the first optical sensor 40a, it is detected by the first optical sensor 40a. The width W1 of the small area 157, which is located in the vertical direction, becomes smaller in proportion to the amount of deviation compared to the normal position (intermediate linear area A1). Therefore, the direction and amount of positional deviation in the first direction D1 can be detected based on the width W1.

Furthermore, the boundary between the small region 157 and the left small region 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 in 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 area 157 in the second direction D2) is determined according to the direction and amount of shift. The detection position of changes. Therefore, the direction and amount of deviation in the second direction D2 can be detected based on the detected position of the boundary.

Note that in an alternative embodiment in which the boundary between the small region 157 and the right small region 159 is orthogonal to the second direction D2, the boundary between the small region 157 and the right small region 159 (in other words, the second direction D2 ), the direction and amount of deviation in the second direction D2 can be detected. Furthermore, the boundary between the small region 157 and the left small region 158 is not orthogonal to the second direction D2, and the boundary between the small region 157 and the right small region 159 is not orthogonal to the second direction D2. In an alternative embodiment, the direction and amount of deviation in second direction D2 can be detected based on the detected positions of both the start and end points of small region 157 in second direction D2. Although detailed description is omitted, the misregistration detection function can be provided based on the same principle even if other portions of the first region 154 (portions other than the small regions 157 to 159) are used. Furthermore, in another alternative embodiment, the width W1 of the small region 157 may be set uniquely according to the position in the direction intersecting the second direction D2 (hereinafter also referred to as the intersecting direction).

The second area 155 provides a defocus detection function for the optical sensors 40a, 40b. The second region 155 comprises a plurality of white first lines 161 and a plurality of white second lines 162 . Each second line 162 is thinner than any of the plurality of first lines 161 .

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

Based on the marking-related light obtained based on such second area 155, when both the first line 161 and the second line 162 are not detected and when the first line 161 and the second line 162 are detected, it can be determined that the detected position of the object 90 to be sorted is defocused. Whether or not the first line 161 and the second line 162 can be detected is determined, for example, by binarization processing using a threshold based on the signals acquired by the optical sensors 40a and 40b. Alternatively, it may be done by an edge detection process.

A third area 156 provides a white balance check function. Specifically, the third area 156 is a white area, and the current white balance setting can be confirmed from the marking-related light gradation value obtained based on the third area 156 . Further, if necessary, the white balance is corrected so that the gradation value of the marking-related light obtained based on the third area 156 becomes an arbitrary reference value (for example, the reference value of the gradation value 255). may Since the third area 156 is a white area as a whole, even if the optical sensors 40a and 40b are misaligned, the white balance checking function can be provided without being affected by the misalignment.

At least one of regions 154-156 may provide a light intensity detection function for light sources 30a, 30b. That is, based on the marking-related light obtained through at least one of the regions 154-156, the light amounts of the light sources 30a and 30b may be detected. In this case, the processing of the calibration unit 86 may be performed based on the detected light amount, as in the first embodiment. In this case, the calibration unit 86 may perform light amount adjustment using the diaphragms of the lenses of the optical sensors 40a and 40b. Alternatively, the calibration unit 86 may detect that at least some of the light emitting elements 32a and 32b are in a non-lighting state due to failure, deterioration, or the like, as the light amount abnormality based on the detected light amount.

FIG. 6 shows examples of various markings that may be used in place of marking 153. FIG. Examples 1 to 4 are examples of marking that can provide a positional deviation detection function and a white balance confirmation function. Examples of markings that can be provided. In examples 5 to 8, as described above, a defocus detection function is added by combining relatively thick lines and relatively thin lines. Examples 1-3, 5-8 are monochrome markings in which only black and white are used, and Example 4 is a color marking having multiple colors other than black and white. However, with respect to Examples 1-8 shown in FIG. 6, the colors of the markings are not particularly limited and any number and type of colors can be used for the markings. This point also applies to the marking 153 shown in FIG. Furthermore, the outer contour and inner shape of the marking are not limited to the various examples shown in FIGS. 5 and 6, and can be arbitrarily set as long as at least part of the functions described above can be provided.

Although the embodiments of the present disclosure have been described above, the above-described embodiments are intended to facilitate understanding of the present teachings and are not intended to limit the present invention. The present invention may be modified and improved without departing from its spirit, and the present invention includes equivalents thereof. In addition, any combination or any omission of each component described in the claims and the specification within the range that at least part of the above problems can be solved or at least part of the effect is achieved is possible.

For example, the first light source 30a and the second light source 30b may be composed of any type of light emitting element instead of LEDs. The light emitting element may be, for example, a fluorescent lamp, an EL, or the like. Moreover, the sorting machine 10 may be provided with a light source for irradiating near-infrared rays instead of or in addition to the first light sources 30a and 30b. In this case, an additional intermediate member having a function equivalent to that of the intermediate member 50 may be provided for the near-infrared light source, and the near-infrared light source may be subjected to calibration processing and notification processing. An additional optical sensor may also be provided for detecting near-infrared light. In this case, the processing of the detection unit 82, the first correction unit 83, and the second correction unit 84 may be performed with respect to the additional optical sensor. In addition, the light source used in the sorting machine 10 is not limited to the configuration that emits visible light or near-infrared light as exemplified above, and emits electromagnetic waves of any wavelength (in other words, light in a broad sense). may be configured to In this case, any type of sensor may be employed to detect the electromagnetic waves emitted by the light source, and an intermediate member having a function equivalent to that of the intermediate member 50 for at least one of the light source and the sensor. A member may be provided.

Additionally, the first layer 51 of the intermediate member 50 may be omitted. Alternatively, intermediate member 50 may comprise a single layer region and a multiple layer region. Furthermore, at least 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 part of the notification process described above may be omitted.

Also, 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 an omission, the light associated with the item 90 to be sorted may be one of reflected light and transmitted light. Conversely, the number of light sources may be an arbitrary number of 2 or more on the front side and an arbitrary 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 any number of 2 or more on the rear side. The number of light sources and optical sensors may be the same on the front side and the number on the rear side, or may be different. Also, the total number of front-side and rear-side light sources and the total number of front-side and rear-side optical sensors may be the same or different.

Furthermore, the number of intermediate members 50 to be installed can be any number equal to or greater than one.

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

10... Optical sorting machine 20... Optical detector 21a, 21b... Transparent member 30a... First light source 30b... Second light source 31a, 31b... Light 32a, 32b. ..Light emitting element 40a...First optical sensor 40b...Second optical sensor 41a, 41b...Light receiving element 50...Intermediate member 51...First layer 52...Second Layer of 53...Marking 54...First unit area 55...Second unit area 71...Storage tank 72...Feeder 73...Chute 74...Good product discharge gutter 75. .. Defective product discharge gutter 76... Sorting unit 77... Ejector 78... Air 80... Controller 81... Judging unit 82... Detecting unit 83... First correcting unit 84. .. Second correction section 85... Color correction section 86... Calibration section 88... Notification section 90, 91, 92... Objects to be sorted 95... Transfer path 153... Marking 154 ...first area 155...second area 156...third area 157...small area 158...left small area 159...right small area 161...first area Lines 162...Second line D1...First direction D2...Second direction V1...Total field of view of first and second optical sensors V2...First direction 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 (8)

An optical sorter,
a light source configured to irradiate light onto the objects to be sorted being transported on the transport path;
an optical sensor configured to detect light emitted from the light source and associated with the item to be sorted;
a determination unit configured to determine foreign matter and/or defective items for the items to be sorted based on a signal acquired by the optical sensor for light associated with the items to be sorted;
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 detection of the light associated with the object to be sorted; an intermediate member having markings;
The optical sorter, wherein the optical sensor is further configured to detect marking-related light emitted from the light source and obtained through the marking. The optical sorting machine according to claim 1,
An optical sorting machine comprising a detection unit configured to detect the state of the optical sensor based on a detection result of the marking-related light. The optical sorting machine according to claim 1 or claim 2,
An optical sorting machine comprising a calibration unit configured to be able to perform calibration based on a detection result of the marking-related light. The optical sorting machine according to any one of claims 1 to 3,
The light source is
a first light source arranged on a first side relative to the transfer path of the items to be sorted;
a second light source positioned on a second side opposite the first side;
the optical sensor comprises at least one of a first optical sensor located on the first side and a second optical sensor located on the second side;
The intermediate member is optically non-transmissive, and substantially prevents light from reaching the optical sensor through the intermediate member from the transport path side. The optical sorting machine according to any one of claims 1 to 4,
The marking is
At least one first unit area having a first color and a certain size and at least one second unit area having a second color different from the first color and having the certain size 2 unit areas, and
An optical sorting machine, wherein the first unit area and the second unit area are arranged one-dimensionally or two-dimensionally in a predetermined appearance pattern. An optical sorter,
a light source configured to irradiate light onto the objects to be sorted being transported on the transport path;
a first optical sensor configured to detect light emitted from the light source and associated with the item to be sorted;
a determination unit configured to determine foreign matter and/or defective items for the items to be sorted based on a signal acquired by the optical sensor for light associated with the items to be sorted;
arranged at a position between the light source and the transport 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 detection of the light associated with the object to be sorted; an intermediate member having markings;
and a second optical sensor configured to detect marking-related light emitted from said light source and obtained through said marking. An optical sorter,
a light source configured to irradiate light onto the objects to be sorted being transported on the transport path;
an optical sensor configured to detect light emitted from the light source and associated with the item to be sorted;
a determination unit configured to determine the quality of the item to be sorted based on a signal acquired by the optical sensor regarding light associated with the item to be sorted;
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 detection of the light associated with the object to be sorted; an intermediate member having 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 a plurality of regions,
An optical sorting machine, wherein each of the plurality of areas is configured to provide at least one or more functions for ensuring determination performance of the determination unit based on the marking-related light. An optical sorting machine 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 deviation detection function of the optical sensor, a focus deviation detection function of the optical sensor, and a white balance confirmation function of the optical sensor. Optical sorting machine.

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