An improved sorting device for agricultural products using a combination of ejectors and blowing nozzles

Abstract

The present invention relates to a sorting device for sorting objects from a bulk flow of agricultural products, the sorting device comprising a unit for bulk transport of the agricultural products, a sensor unit for obtaining sensor data from the bulk flow for recognizing objects, a decision unit for generating a control signal for a separation unit based on the sensor data, and the separation unit for separating objects from the bulk flow according to the control signal, wherein the separation unit comprises at least one ejector and at least one blowing nozzle, wherein the at least one ejector and the at least one blowing nozzle can be controlled independently of each other by the control signal. The invention also relates to a method for sorting objects from a bulk flow of agricultural products and a use.

Description

[0001] AN IMPROVED SORTING DEVICE FOR AGRICULTURAL PRODUCTS USING A COMBINATION OF EJECTORS AND BLOWING NOZZLES

[0002] TECHNICAL FIELD

[0003] The invention relates to a sorting device for sorting objects from a bulk flow of agricultural products, more specifically for sorting potatoes, vegetables and fruit. The invention also relates to a method for sorting objects from a bulk flow of agricultural products and to a use of the sorting device and / or the method for sorting contaminated potatoes, onions, red beets and carrots.

[0004] PRIOR ART

[0005] Such a sorting device is known, inter alia, from EP 4 021 655 (EP ‘655) .

[0006] EP ‘655 describes a sorting device for sorting agricuiturai products. The sorting device comprises a conveyor belt for the bulk supply of agricultural products. A camera unit is placed above the sorting belt. The camera unit is used to create images of the agricultural products. These images are processed using an image processing unit and based on the images, a decision unit decides whether to control an ejector finger to eject an agricultural product if it does not meet certain criteria.

[0007] This known sorting device has the following disadvantage. An ejector finger has a certain inertia. Therefore, it is necessary that there is sufficient spacing between the agricultural products on the conveyor belt to prevent the ejector finger from ejecting not only the unwanted agricultural product but also the subsequent agricuiturai product. This is particularly disadvantageous if the agricultural products are still contam inated, for example with stones or clods of earth. It is practically unfeasible to place agricultural products and stones on a conveyor belt with sufficient separation. Clods of earth can stick to the agricuiturai products and come loose during movement on the conveyor belt, making it again impossible to guarantee sufficient separation. A sorting device according to EP ‘655 therefore requires that stones and clods of earth be separated from the agricuiturai products in advance and that the agricultural products are placed separately on the conveyor belt. This requires more preparatory steps and a lower throughput speed on the conveyor belt. Another known sorting device is described in DE 195 16 569 ( DE ‘569) . The sorting device from DE ‘569 is intended for removing foreign objects from flakes before yarns are spun from the fiakes. The foreign objects are biown out of the fiakes using the biowing nozzies. Oniy iight objects can be biown away using the blowing nozzies. Since the fiakes are also light, it cannot be guaranteed that no flakes will be blown along. The fiakes are deflected from the container for foreign objects using flaps. These flaps block the entire channel for the flakes, making them unsuitable for selectively deflecting the foreign objects towards the container. This device therefore has the disadvantage that no pure sorting of foreign objects is possible.

[0008] Another sorting device is disclosed in WO 98 / 31477 (WO ‘477) . The sorting device from WO ‘477 is used for sorting granular products such as peas, nuts, raisins, etc. This sorting device has the disadvantage that it only uses blowing nozzles, so that only light objects can be separated.

[0009] The present invention aims to solve at least some of the above problems or drawbacks.

[0010] SUMMARY OF THE INVENTION

[0011] I n a first aspect, the present invention relates to a sorting device according to claim 1 .

[0012] An ejector is advantageous for removing heavy and / or large objects but has the disadvantage that the ejector has a certain inertia and therefore cannot always be moved quickly enough after ejecting an object to a position where the ejector does not hinder the agricultural products. A blowing nozzle has the advantage that im mediately after actuating the blowing nozzle, a free passage of the agricultural products is possible, but on the other hand, it has the disadvantage that a blowing nozzle is mainly suitable for light objects. Because the objects can be recognized using the sensor data, an optimal choice can be made between the use of the at least one ejector, the at least one blowing nozzle, or the at least one blowing nozzle and the at least one ejector in a sorting device according to claim 1. This makes the sorting device particularly suitable for removing, for example, stones and clods of earth, even if they immediately precede or follow an agricultural product on the unit for bulk transport of the agricultural products. Preferred embodiments of the device are set out in ciaims 2 up to and including 9.

[0013] I n a second aspect, the present invention relates to a method according to claim 10.

[0014] This method has the advantage, inter aiia, that by using a separation unit that includes at least one blowing nozzle and at least one ejector, and by the decision unit generating a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle based on the recognized objects, it is possible to also sort objects that are close to agricultural products on the unit for bulk transport of the agricultural products out of the bulk flow. As a result, it is also not necessary to place the agricultural products and objects with a certain separation on the unit for bulk transport of the agricultural products, allowing for a higher throughput speed.

[0015] Preferred forms of the method are described in dependent claims 11 up to and including 14.

[0016] I n a third aspect, the present invention relates to a use according to claim 15.

[0017] This use results in an advantageous sorting of contam inated agricultural products, such as potatoes, carrots, red beets or onions, because also objects, such as stones and clods of earth, that are close to agricultural products on the unit for bulk transport of the agricultural products, can be sorted out from the bulk flow of agricultural products, enabling a higher throughput speed during sorting.

[0018] DESCRIPTION OF THE FIGURES

[0019] Figure 1 shows a side view of a sorting device according to an embodiment of the present invention.

[0020] Figure 2 shows a side view of a sorting device according to a second embodiment of the present invention.

[0021] Figure 3 shows a side view of a sorting device according to a third embodiment of the present invention. Figure 4 shows a side view of a sorting device according to a fourth embodiment of the present invention.

[0022] DETAILED DESCRIPTION

[0023] Unless otherwise defined, all terms used in the description of the invention, including technical and scientific terms, have the meanings as com monly understood by a person skilled in the art to which the invention pertains. For a better assessment of the description of the invention, the following terms are explained explicitly.

[0024] I n this document, “a” and “the” refer to both the singular and the plural, unless the context presupposes otherwise. For example, “a segment” means one or more than one segment.

[0025] The terms “comprise,” “comprising,” “consist of,” “consisting of,” “provided with,” “include,” “including,” “contain,” “containing,” are synonyms and are inclusive or open terms that indicate the presence of what follows, and which do not exclude or prevent the presence of other components, characteristics, elements, members, steps, as known from or disclosed in the prior art.

[0026] Quoting numeric intervals by the endpoints includes all integers, fractions, and / or real numbers between the endpoints, including those endpoints.

[0027] I n the context of this document, an agricultural product refers to a product resulting from agricultural activities. Agricultural products can include grains, vegetables, fruits and nuts. A subgroup of agricultural products are PVF products, where P stands for potato, V for vegetable, and F for fruit. A subset within PVF products are harvested products. A harvested product is a crop that is harvested by harvesting. The mature crop is usually removed from the ground during harvesting, often with the aid of special agricultural machinery. Non-lim iting examples of harvested products are potatoes, carrots, onions and red beets.

[0028] I n the context of this document, bulk flow refers to a steady supply of bulk goods, more specifically agricultural products, on a transportation device.

[0029] I n the context of this document, an object refers to an item that is located in the bulk flow of agricultural products. An object can be pollution, such as wood, stones, clods of earth or dead animals. An object can, depending on the application, be an agricultural product that does not meet the requirements for the agricultural product, for example, too small, rotten or damaged, and therefore needs to be removed from the bulk flow of agricultural products.

[0030] I n a first aspect, the invention concerns a sorting device for sorting objects from a bulk flow of agricultural products.

[0031] The agricultural products are preferably PVF products, more preferably harvested products.

[0032] The sorting device comprises a unit for the bulk transport of the agricultural products. The unit for bulk transport of the agricultural products is, for example, a conveyor belt, a roller conveyor, a chute, or a combination thereof. The unit for bulk transport of the agricultural products is preferably a conveyor belt or a roller conveyor or a combination of both.

[0033] The sorting device further comprises a sensor unit for obtaining sensor data from the bulk flow for recognizing objects. The sensor unit is, for example, a laser for determ ining dimensions of an object, whereby in case of deviating dimensions or shapes it can be determined that the object is not a desired agricultural product. The sensor unit is, for example, a magnetic sensor for measuring magnetic properties of an object, which differ from an agricultural product and allow the object to be distinguished from the agricultural product. The sensor unit is, for example, a sensor for measuring the spectral response after illum inating an object with a calibrated light source, where an object is recognized based on its spectral response. The sensor unit is, for example, a camera for capturing images in the visible spectrum of light. The object can for example be visually recognized here. It will be apparent to one skilled in the art that other types of sensor units are also suitable for detecting objects in the bulk flow of agricultural products. Optionally, the sensor unit comprises a combination of various sensors.

[0034] The sorting device comprises a decision unit for generating a control signal for a separation unit based on the sensor data obtained by the sensor unit. The decision unit comprises a processing unit, such as a processor or a controller, and working memory. The decision unit is com municatively connected to the sensor unit, for exampie via a serial bus. Alternatively, the image processing unit and the decision unit can be an integrated unit.

[0035] The sorting device comprises a separation unit for separating objects from the bulk flow according to the control signal. The separation unit is preferably placed at an end of the unit for bulk transport of the agricultural products. The separation unit comprises means for modifying a trajectory of an object in the bulk flow of agricultural products. The said means can be controlled by the control signal. Preferably, the mentioned means are one or more ejectors. The one or more ejectors are, for example, linearly movable actuators. Another example of an ejector is an ejector finger, wherein the ejector finger is rotatabie about a rotation point. Preferably, the one or more ejectors are ejector fingers, i n the case of m ultiple ejectors, the ejectors are preferably independently controllable by the control signal. The one or more ejectors are movable from a first position to a second position and back by means of the control signal. I n the first position, an ejector is located in the path of the bulk flow of agricultural products, allowing an object to be tapped in the bulk flow and removed from the bulk flow of agricultural products. I n the second position, the ejector is located outside the path of the bulk flow of agricultural products, so that the agricultural products are not obstructed in their path. Preferably, the sorting device comprises a separating plate at the end of the unit for bulk transport of the agricultural products, where objects are forced towards a first side of the separating plate when an ejector is in the first position and where agricultural products can move unhindered to a second opposite side of the separating plate when an ejector is in the second position. The separation unit is comm unicatively connected to the decision unit for transmitting the control signal. The separation unit is preferably connected to the decision unit with a serial bus. Non-lim iting examples of a suitable serial bus are EtherCat, CAN, Modbus, Profibus. Alternatively, the mentioned means of the separation unit are connected to a control output of the decision unit. Preferably, each individual means is connected to a separate control output.

[0036] According to a preferred embodiment, the sorting device comprises at least one ejector and at least one blowing nozzle. The at least one ejector and the at least one blowing nozzle can be controlled independently of each other by means of the control signal. If there are m ultiple ejectors, preferably the m ultiple ejectors are independently controllable. If there are m ultiple blowing nozzles, preferably the multiple blowing nozzles are independently controllable. An ejector is advantageous far removing heavy and / or iarge objects but has the disadvantage that the ejector has a certain inertia and therefore cannot always be moved quickiy enough after ejecting an object to a position where the ejector does not hinder the agricultural products. A biowing nozzle has the advantage that im mediately after actuating the blowing nozzle, a free passage of the agricultural products is possible, but on the other hand, it has the disadvantage that a blowing nozzle is mainly suitable for light objects. Because the objects can be recognized using the sensor data, an optimal choice can be made between the use of the at least one ejector, the at least one blowing nozzle, or the at least one blowing nozzle and the at least one ejector.

[0037] For example, a light or small object that is isolated or located just before or just after an agricuiturai product on the unit far bulk transport of the agricultural products can be sorted from the bulk flow of agricultural products using only the at least one blowing nozzle. The at least one blowing nozzle can be controlled sufficiently accurately and sufficiently briefly that the at least one blowing nozzle has no influence on the agricultural product.

[0038] For example, a heavy and / or large object that is isolated on the unit for bulk transport of the agricuiturai products can be sorted out from the bulk flow of agricultural products using only the at least one ejector. The ejector will not hinder agricultural products.

[0039] For example, a heavy and / or large object that is located right before or right after an agricultural product on the unit for bulk transport of the agricultural products can be sorted out from the bulk flow of agricultural products using the at least one ejector. The at least one ejector is preferably not fully extended, but only partially moved from the second position to the first position, so that the heavy and / or large object can just be touched by the at least one ejector, and returned to the first position quickly enough, so that agricuiturai products are not hindered in their trajectory. Optionally, the at least one blowing nozzle can be used to blow on the object, in support of the at least one ejector.

[0040] It is clear that in the examples described above, in the case of m ultiple ejectors and / or m ultiple blowing nozzles, only one or more of the ejectors and / or blowing nozzles can be used, depending on a size and / or position of the object on the unit for bulk transport of the agricultural products.

[0041] The sorting device is therefore particularly suitable for removing, for example, stones and clods of earth, even if they immediately precede or follow an agricultural product on the unit for bulk transport of the agricultural products.

[0042] According to a preferred embodiment, the unit for bulk transport of the agricultural products comprises a conveyor belt or a roller conveyor. The separation unit is placed at an end of the conveyor beit or roller conveyor. The at least one ejector can be moved to the end of the conveyor beit or roller conveyor and back. The at least one ejector is m ovable from the second position to the first position and back, wherein the first position is located near the end of the conveyor belt. The first position and the second position are as described earlier. The at least one blowing nozzle of the separation unit is directed towards the end of the conveyor beit or roller conveyor. Preferably, the sorting device comprises a separating plate that is placed near the end of the conveyor belt or roller conveyor. The separating piate is as in a previously described embodiment. The first side of the separating plate is directed towards the end of the conveyor belt or roller conveyor.

[0043] This embodiment is particularly advantageous for separating objects from the bulk flow of agricultural products, where a majority of the objects are heavier than the agricultural products. As a result, the objects are inclined to fall closer to the end of the conveyor belt or roller conveyor than the agricultural products. An example is clods of earth that often weigh more than potatoes. A trajectory of the objects is modified by the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle, causing the objects to fall even closer to the end of the conveyor belt or roller conveyor than the agricultural products.

[0044] According to an alternative embodiment, the unit for bulk transport of the agricultural products comprises a conveyor belt or a roller conveyor. The separation unit is placed under an end of the conveyor belt or roller conveyor. The at least one ejector can be moved to the end of the conveyor beit or roller conveyor and back. The at least one ejector is m ovable from the second position to the first position and back, wherein the second position is located near the end of the conveyor beit. The first position and the second position are as described earlier. The at least one blowing nozzle is placed under the end of the conveyor belt or roller conveyor. The at least one blowing nozzle Is directed in a direction away from the end of the conveyor belt or roller conveyor. Preferably, the sorting device comprises a separating plate that is placed near the end of the conveyor belt or roller conveyor. The separating plate is as in a previously described embodiment. The second side of the separating plate is directed towards the end of the conveyor belt or roller conveyor.

[0045] This embodiment is particularly advantageous for separating objects from the bulk fiow of agricultural products, where a majority of the objects are lighter than the agricultural products. As a result, the objects are inclined to fail further from the end of the conveyor belt or roller conveyor than the agricultural products. An example is pebbles, which usually weigh less than potatoes. A trajectory of the objects is modified by the at least one ejector, or the at least one biowing nozzie, or the at least one ejector and the at least one biowing nozzle, causing the objects to fail even further from the end of the conveyor belt or roller conveyor than the agricultural products.

[0046] A similar advantage as for this embodiment can be obtained by a hybrid embodiment, wherein the at least one blowing nozzle is placed under the end of the conveyor belt or roller conveyor and wherein the at least one ejector is placed near the end of the conveyor belt or roller conveyor. The at least one ejector is still movable towards the end of the conveyor belt or the roller conveyor and back. The function of the ejector is different in this hybrid embodiment. I n the first position, the elector obstructs the trajectory of the agricultural products, causing the agricultural products to fall even closer to the end of the conveyor belt or roller conveyor. I n the second position, the objects can follow their trajectory unhindered and fail further from the end of the conveyor belt or roller conveyor, therein supported by the at least one blowing nozzle. I n this hybrid embodiment, sim ultaneously actuating the at least one ejector and the at least one blowing nozzle is not as advantageous.

[0047] According to a preferred embodiment, the sorting device comprises at least one auxiliary blowing nozzle. Preferably, there is an auxiliary blowing nozzle for each blowing nozzle. The at least one auxiliary blowing nozzle is directed in an opposite direction to the at least one blowing nozzle. The directions of the at least one blowing nozzle and the at least one auxiliary blowing nozzle are opposite when projected onto a horizontal plane. The at least one auxiliary blowing nozzle can preferably be controlled independently of the at least one ejector and of the at least one blowing nozzle by a control signal from the decision unit. If there are multiple auxiliary blowing nozzles, preferably the auxiliary blowing nozzles are independently controllable by a control signal from the decision unit.

[0048] This embodiment is particularly advantageous in a situation where a heavy and / or large object needs to be sorted from the bulk flow of agricultural products that is located just before an agricultural product on the unit for bulk transport of the agricultural products. As in a previously described example, a heavy and / or large object that lies immediately in front of an agricultural product on the unit for bulk transport of the agricultural products can be sorted out from the bulk flow of agricultural products using the at least one ejector. There is a chance that due to the inertia of the ejector, the ejector has not fully returned to the second position, causing an agricultural product to be sorted incorrectly from the bulk flow. Optionally, the at least one auxiliary blowing nozzle can be controlled after sorting the heavy and / or large object from the bulk flow, in order to force agricultural products in a direction other than the objects, even if the at least one ejector has not yet fully returned to the second position. This is particularly advantageous in combination with only partially moving the at least one ejector from the second position to the first position.

[0049] It is clear that in the case of m ultiple ejectors and / or multiple auxiliary blowing nozzles, only one or more of the auxiliary blowing nozzles can be used, depending on a size and / or position of an agricultural product on the unit for bulk transport of the agricultural products.

[0050] According to a preferred embodiment, the sorting device comprises m ultiple ejectors and multiple blowing nozzles. The m ultiple ejectors and m ultiple blowing nozzles are evenly distributed in a transverse direction at an end of the unit for bulk transport of the agricultural products. The transverse direction is perpendicular to a direction in which the agricultural products are moved by the mentioned unit. There are at least 15 ejectors and at least 20 blowing nozzles per meter.

[0051] Preferably, there are at least 16 ejectors per meter, more preferably at least 17 ejectors per meter, even more preferably at least 18 ejectors per meter and even more preferably at least 19 ejectors per meter. Preferably, there are at least 21 blowing nozzles per meter, more preferably at least 22 blowing nozzles per meter, even more preferably at least 23 blowing nozzles per meter and even more preferably at least 25 blowing nozzles per meter.

[0052] This embodiment is advantageous for accurately sorting objects from the bulk flow, regardless of a position of the object on the unit for transporting agricultural products in the transverse direction. There is always at least one blowing nozzle and always at least one ejector at a distance of no more than a few centimeters, seen in the transverse direction.

[0053] This embodiment is particularly advantageous if the ejectors can be controlled independently of each other and the blowing nozzles can be controlled independently of each other by the control signal. This makes it only necessary to control one or more ejectors and / or blowing nozzles at the location of the object, resulting in energy savings. This is additionally advantageous because objects can be sim ultaneously sorted from the bulk flow at various locations along the width direction of the unit for transporting the agricultural products, allowing for a higher capacity of the sorting device.

[0054] According to a preferred embodiment, the blowing nozzles are directed downwards. The blowing nozzles have a blowing direction that forms an angle of at least 15° with a horizontal line.

[0055] This embodiment is particularly advantageous in combination with embodiments wherein objects and agricultural products fall downwards at an end of the unit for bulk transport of the agricultural products. By directing the blowing nozzles downwards, an object or, if applicable, an agricultural product is forced to fall even faster, resulting in a greater impact on the trajectory of the object or the agricultural product and allowing for more accurate sorting of objects from the bulk flow.

[0056] Preferably, the blowing direction forms an angle of at least 16° with the horizontal line, more preferably at least 17°, even more preferably at least 18° and even more preferably at least 19° .

[0057] According to a further embodiment, the blowing direction makes an angle of at most 29° with the horizontal line, preferably at most 27°, more preferably at most 25° , even more preferably at most 23° and even more preferably at most 21 ° . A larger angle than 29° is not useful because it would place the nozzle too close and at large angles almost above the end of the unit for bulk transport of the agricultural products. As a result, there is only a minimal time slot in which the blowing nozzle can influence the trajectory of the objects and, if applicable, the agricultural products. Furthermore, with an angle greater than 29°, the blowing nozzle may not sufficiently influence the horizontal component of the trajectory of the objects and, if applicable, the agricultural products, which is detrimental to the sorting of the objects from the bulk flow.

[0058] According to a preferred embodiment, the auxiliary blowing nozzles are directed downwards. The auxiliary blowing nozzle have a blowing direction that forms an angle of at least 15° with a horizontal line. Preferably, the auxiliary blowing nozzles have a blowing direction that forms an angle of no more than 29° with the horizontal line.

[0059] Preferably, the blowing direction forms an angle of at least 16° with the horizontal line, more preferably at least 17°, even more preferably at least 18° and even more preferably at least 19° .

[0060] Preferably, the blowing direction makes an angle of at most 29° with the horizontal line, preferably at most 27° , more preferably at most 25° , even more preferably at most 23° and even more preferably at most 21 °.

[0061] This embodiment has the same advantages in influencing the trajectory of the agricultural products as in influencing the trajectory of the objects as in the previously described embodiments.

[0062] According to a preferred embodiment, the sensor unit is an image acquisition unit for capturing images of the bulk flow on the unit for bulk transport of the agricultural products. The image acquisition unit preferably comprises a camera in the visible spectrum of light. Optionally, the image acquisition unit comprises m ultiple cameras. Optionally, the camera of the image acquisition unit is a camera for three-dimensional imaging. Preferably, the image acquisition unit is placed in a non-light-transm itting housing. The non- iight-transm itting housing is advantageous for controlled lighting conditions when capturing the images. The non-light-transm itting housing is placed on the unit for bulk transport of the agricultural products. Alternatively, the image acquisition unit is placed at and under an end of the unit for bulk transport of the agricultural products. I n this embodiment, images of the bulk flow are taken during the fail of the agricultural products from the unit for bulk transport of the agricultural products. Preferably, this embodiment comprises two cameras, with the cameras facing each other. This is advantageous for capturing images of m ultiple sides of the agricultural products and objects between the agricultural products. Preferably, the image acquisition unit comprises a light source for illum inating the agricultural products and objects among the agricultural products. More preferably, the light source is a calibrated light source. A non-limiting example of a calibrated light source is D65 as defined in I SO 10526:2007.

[0063] The sorting device further comprises an image processing unit for recognizing the agricultural products in the images made by the image acquisition unit. The image processing unit comprises a processing unit, such as a processor or a controller, and working memory. The image processing unit is com municatively connected to the image acquisition unit, for example via a serial bus. Alternatively, the image acquisition unit and the image processing unit are an integrated unit. Preferably, the image processing unit comprises a computer program that, when executed on the processing unit of the image processing unit, performs a recognition algorithm based on artificial intelligence. The recognition algorithm has been trained with a training set of pre-made images. The training set comprises images of the agricultural products.

[0064] I n this embodiment the decision unit is preferably connected com municatively to the image processing unit, for example via a serial bus. Alternatively, the image processing unit and the decision unit can be an integrated unit.

[0065] The image processing unit is configured to recognize the objects in the said images made of the bulk flow. Preferably, the image processing unit comprises a computer program that, when executed on the processing unit of the image processing unit, performs a recognition algorithm based on artificial intelligence. The recognition algorithm has been trained with a training set of pre-made images. The training set comprises images of the agricultural products and images of typical objects that need to be sorted from the bulk flow of agricultural products.

[0066] According to a further embodiment, the image processing unit is configured to determine a volume of the objects. The volume of the objects is estimated based on the images created by the image acquisition unit. This is advantageous when generating a control signal by the decision unit, wherein a most suitable control signal is generated depending on the determ ined volume of the object, for example a control signal wherein the at least one blowing nozzle, or the at least one ejector, or the at least one blowing nozzle and the at least one ejector are controlled.

[0067] This embodiment is particularly advantageous in combination with a roller conveyor, through which an object rolls and through which images of m ultiple sides of the object can be taken by the image acquisition unit. This allows for a more accurate determination of the volume of the object.

[0068] Preferably, the image processing unit is configured to determ ine the volume of the agricultural products. This has a sim ilar advantage as described above for the objects.

[0069] According to a preferred embodiment, the decision unit is configured to determ ine a weight of the objects based on a specific weight associated with the objects. After determ ining the volume of the object, the weight of the object can be easily calculated by m ultiplying the volume by the specific weight. Each type of object that can be recognized by the image processing unit is associated with a specific weight. With a recognition algorithm based on artificial intelligence, a specific weight is preferably associated with each class of objects during training or after training.

[0070] Only taking into account the volume when generating the control signal can in some cases result in less optimal control of the at least one ejector and the at least one blowing nozzle. For example, an object that needs to be sorted from the bulk flow can have a large volume but still have a low weight. This makes these objects suitable for being sorted out of the bulk flow using the at least one ejector nozzle, thereby avoiding a potential risk of incorrectly sorting an agricultural product from the bulk flow due to the inertia of the at least one ejector.

[0071] Preferably, the decision unit is configured to generate the control signal based on the determ ined volume and the determ ined weight. This is advantageous in the case of objects with a large volume and an average weight or objects with an average volume and a low weight, for optimal control of the at least one ejector and the at least one blowing nozzle.

[0072] Preferably, the image processing unit is configured for determining the weight of the agricultural products. This has a sim ilar advantage as described above for the objects. According to a preferred embodiment, the decision unit of the sorting unit is configured to perform a method according to the second aspect. it will be apparent to one skilled in the art that a sorting device according to the first aspect is not only suitable for sorting objects from the bulk flow of agricultural products, but also for sorting a subcategory of agricultural products from the bulk flow. A subcategory can, for example, comprise all agricultural products with an irregular shape, damage, a weight in a predetermined range, a volume in a predetermined range, etc.

[0073] I n a second aspect, the invention relates to a method for sorting objects from a bulk flow of agricultural products.

[0074] The agricultural products are preferably PVF products, more preferably harvested products.

[0075] The method comprises the steps of: supplying the bulk flow of agricultural products on a unit for bulk transport of the agricultural products; creating sensor data from the bulk flow using a sensor unit; generating a control signal by a decision unit for separating the objects from the bulk flow based on the sensor data; separating the objects from the bulk flow according to the control signal using a separation unit.

[0076] The decision unit comprises a processing unit, such as a processor or a controller, and working memory. The decision unit is com m unicatively connected to the sensor unit, for example via a serial bus.

[0077] The separation unit is preferably placed at an end of the unit for bulk transport of the agricultural products. The separation unit comprises means for modifying a trajectory of an object in the bulk flow of agricultural products. The said means can be controlled by the control signal. Preferably, the mentioned means are one or more ejectors. I n the case of m ultiple ejectors, the ejectors are preferably independently controllable by the control signal. The one or more ejectors are movable from a first position to a second position and back by means of the control signal. I n the first position, an ejector is located in the path of the bulk flow of agricultural products, allowing an object to be tapped in the bulk flow and removed from the bulk flow of agricultural products. I n the second position, the ejector is located outside the path of the bulk flow of agricultural products, so that the agricultural products are not obstructed in their path. The separation unit is com municatively connected to the decision unit for transm itting the control signal.

[0078] According to a preferred embodiment, the separation unit comprises at least one ejector and at least one blowing nozzle. The at least one ejector and the at least one blowing nozzle can be controlled independently of each other by means of the control signal. If there are m ultiple ejectors, preferably the multiple ejectors are independently controllable. If there are m ultiple blowing nozzles, preferably the m ultiple blowing nozzles are independently controllable.

[0079] The method comprises the additional steps of recognizing the objects on the unit for bulk transport of the agricultural products, wherein, on the basis of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle.

[0080] The objects in the bulk flow are recognized using the sensor data.

[0081] An ejector is advantageous for removing heavy and / or large objects but has the disadvantage that the ejector has a certain inertia and therefore cannot always be moved quickly enough after ejecting an object to a position where the ejector does not hinder the agricultural products. A blowing nozzle has the advantage that im mediately after actuating the blowing nozzle, a free passage of the agricultural products is possible, but on the other hand, it has the disadvantage that a blowing nozzle is mainly suitable for light objects. Because the objects are recognized in the bulk flow, an optimal choice can be made by the decision unit between the use of the at least one ejector, the at least one blowing nozzle, or the at least one blowing nozzle and the at least one ejector. We refer to the previously described examples in the context of a sorting device according to the first aspect.

[0082] This method therefore has the advantage, inter alia, that it is possible to also sort objects that are close to agricultural products on the unit for bulk transport of the agricultural products out of the bulk flow. As a result, it is also not necessary to place the agricultural products and objects with a certain separation on the unit for bulk transport of the agricultural products, allowing for a higher throughput speed

[0083] It is clear that in the examples described above, in the case of m ultiple ejectors and / or m ultiple blowing nozzles, only one or more of the ejectors and / or blowing nozzles can be used, depending on a size and / or position of the object on the unit for bulk transport of the agricultural products.

[0084] According to a preferred embodiment, the sensor data is images that are made of the bulk flow using an image acquisition unit. The image acquisition unit preferably comprises a camera in the visible spectrum of light. Preferably, the image acquisition unit comprises a light source for illum inating the agricultural products and objects among the agricultural products. More preferably, the light source is a calibrated light source.

[0085] The captured images are processed with the aid of an image processing unit. The image processing unit comprises a processing unit, such as a processor or a controller, and working memory. The image processing unit is com m unicatively connected to the image acquisition unit, for example via a serial bus. Alternatively, the image acquisition unit and the image processing unit are an integrated unit. The agricultural products are recognized in the bulk flow by the image processing unit. The objects are recognized in the bulk flow by the image processing unit. The image processing unit performs a recognition algorithm based on artificial intelligence on the processing unit. The recognition algorithm has been trained with a training set of pre-made images. The training set comprises images of the agricultural products and images of typical objects that need to be sorted from the bulk flow of agricultural products.

[0086] The method comprises the additional step of determ ining a volume of the objects. The volume of the objects is estimated based on the images created by the image acquisition unit. The image processing unit executes an algorithm on its processing unit to determ ine the volume of the object. Based on the recognized objects and the volume of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle. This embodiment is advantageous for optima! control of the at least one blowing nozzle and the at least one ejector depending on the determined volume of the object. For example, the decision unit generates a control signal for the at least one blowing nozzle for objects with a small volume, and for objects with a large volume, at least a control signal for the at least one ejector.

[0087] This embodiment is particularly advantageous in combination with rolling an object, for example on a roller conveyor, whereby the image acquisition unit can make images of several sides of the object. This allows for a more accurate determ ination of the volume of the object.

[0088] Preferably, the volume of the agricultural products is also determined. This has a sim ilar advantage as described above for the objects.

[0089] According to a further embodiment, the method comprises the additional step of determining a weight of the objects. The weight is determ ined based on the determ ined volume, as described in a previous embodiment, and a specific weight associated with the recognized objects. After determ ining the volume of the object, the weight of the object can be easily calculated by the image processing unit or alternatively by the decision unit by m ultiplying the volume by the specific weight. Each type of object that can be recognized by the image processing unit is associated with a specific weight. With a recognition algorithm based on artificial intelligence, a specific weight is preferably associated with each class of objects during training or after training.

[0090] Based on the recognized objects and the weight of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle.

[0091] Only taking into account the volume when generating the control signal can in some cases result in less optimal control of the at least one ejector and the at least one blowing nozzle, as was also explained for the sorting device according to the first aspect. Preferably, the decision unit generates the control signal based on the determ ined volume and the determ ined weight of an object. Preferably, the image processing unit or alternatively the decision unit also determ ines the weight of the agricultural products. This has a similar advantage as described in the first aspect for the objects.

[0092] According to a preferred embodiment, the decision unit takes into account a sequence of the objects and the agricultural products on the unit for bulk transport of the agricultural products, and a spacing between the objects and the agricultural products when generating a control signal for the separation unit. Preferably, the determined volume and / or weight of the object is also taken into account.

[0093] When there is a large distance between the objects and the agricultural products, the objects can be considered as isolated from the agricultural products. A light or small object can, for example, be sorted from the bulk flow of agricultural products using only the at least one blowing nozzle. A heavy and / or large object can, for example, be sorted from the bulk flow of agricultural products using only the at least one ejector.

[0094] I n the case of a small distance or separation, primarily the determined weight and / or volume of the object is important. A light and / or small object can, for example, still be sorted from the bulk flow of agricultural products using only the at least one blowing nozzle. A heavy and / or large object that is located right before or right after an agricultural product on the unit for bulk transport of the agricultural products can be sorted out from the bulk flow of agricultural products using the at least one ejector. The at least one ejector is preferably not fully extended, so that the heavy and / or large object can j ust be touched by the at least one ejector and returned to the first position quickly enough, so that agricultural products are not hindered in their trajectory. Optionally, the at least one blowing nozzle can be used to blow on the object, in support of the at least one ejector. With a heavy and / or large object, it is very advantageous to also take the sequence of the objects into account. If a heavy and / or large object is located just in front of an agricultural product on the unit for bulk transport of the agricultural products, an auxiliary blowing nozzle can be used, as described in a subsequent embodiment.

[0095] I n a further embodiment, the separation unit comprises at least one auxiliary blowing nozzle. Preferably, there is an auxiliary blowing nozzle for each blowing nozzle. The at least one auxiliary blowing nozzle is preferably controlled independently of the at least one ejector and of the at least one blowing nozzle by a control signal from the decision unit, if there are m uitiple auxiliary blowing nozzles, preferably the auxiliary blowing nozzles are controlled independently of each other by a control signal from the decision unit. The at least one auxiliary blowing nozzle is directed in an opposite direction to the at least one blowing nozzle. The directions of the at least one blowing nozzle and the at least one auxiliary blowing nozzle are opposite when projected onto a horizontal plane. Depending on the sequence of the objects and the agricultural products and depending on a volume or a weight of the objects, the decision unit generates a control signal for the at least one auxiliary nozzle.

[0096] This embodiment is particularly advantageous in a situation where a heavy and / or large object needs to be sorted from the buik flow of agricultural products that is located just before an agricultural product on the unit for buik transport of the agricultural products. As in a previously described example, a heavy and / or large object that iies immediately in front of an agricultural product on the unit for bulk transport of the agricultural products can be sorted out from the buik flow of agricultural products using the at least one ejector. There is a chance that due to the inertia of the ejector, the ejector has not fully returned to the second position, causing an agricultural product to be sorted incorrectly from the buik flow. Optionally, the at least one auxiliary blowing nozzle can be controlled after sorting the heavy and / or large object from the bulk flow, in order to force agricultural products in a direction other than the objects, even if the at least one ejector has not yet fully returned to the second position. This is particularly advantageous in combination with only partially moving the at least one ejector from the second position to the first position.

[0097] It is clear that in the case of m ultiple ejectors and / or multiple auxiliary blowing nozzles, only one or more of the auxiliary blowing nozzles can be used, depending on a size and / or position of an agricultural product on the unit for bulk transport of the agricultural products.

[0098] It will be apparent to one skilled in the art that a method according to the second aspect is not only suitable for sorting objects from the buik flow of agricultural products, but also for sorting a subcategory of agricultural products from the bulk flow. A subcategory can, for example, comprise all agricultural products with an irregular shape, damage, a weight in a predeterm ined range, a volume in a predetermined range, etc. One skilled in the art will appreciate that a method according to the second aspect is preferably performed using a sorting device according to the first aspect and that a sorting device according to the first aspect is preferably configured for perform ing a method according to the second aspect. Each feature described in this document, both above and below, can therefore relate to any of the three aspects of the present invention.

[0099] I n a third aspect, the invention concerns a use of a sorting device according to the first aspect and / or a method according to the second aspect for sorting contaminated potatoes, carrots, red beets, or onions.

[0100] This use results in an advantageous sorting of contam inated agricultural products, such as potatoes, carrots, red beets or onions, because also objects, such as stones and clods of earth, that are close to agricultural products on the unit for bulk transport of the agricultural products, can be sorted out from the bulk flow of agricultural products, enabling a higher throughput speed during sorting.

[0101] I n what follows, the invention is described by way of non-lim iting figures illustrating the invention, and which are not intended to and should not be interpreted as limiting the scope of the invention.

[0102] DESCRIPTION OF THE FIGURES

[0103] Figure 1 shows a side view of a sorting device according to an embodiment of the present invention.

[0104] The sorting device (1 ) comprises a unit (2) for the bulk transport of agricultural products. The unit (2) for bulk transport of agricultural products in this embodiment is a conveyor belt that extends in a longitudinal direction. An image acquisition unit is placed on top of the unit (2) for bulk transport of agricultural products. The image acquisition unit is placed in a housing (6) . The housing (6) is non-light-transm itting in order to create controlled conditions for the image acquisition unit. The image acquisition unit further comprises a camera (3). The camera (3) works in visible light. The camera (3) is directed towards the conveyor belt of the unit (2) for bulk transport of agricultural products. With the camera (3) , the image acquisition unit captures images of agricultural products and objects on the unit (2) for bulk transport of agricultural products. The image acquisition unit further comprises a light source (5) for creating good lighting conditions for the camera (3). I n this embodiment, an image processing unit (4) is also placed in the housing (6) . The image processing unit (4) is configured to process the images taken of the agricultural products and objects on the unit (2) for bulk transport of agricultural products. The image processing unit (4) is comm unicatively connected to the image acquisition unit. The sorting device (1 ) further comprises a decision unit (7) . The decision unit (7) generates a control signal for a separation unit (8) based on the images processed by the image processing unit (4) . The separation unit (8) is placed at an end of the unit (2) for bulk transport of agricultural products. The separation unit (8) comprises multiple ejector fingers (9) and multiple blowing nozzles (10) . I n Figure 1 , only one ejector finger (9) and one blowing nozzle (10) are visible each time. The m ultiple ejector fingers (9) can be controlled independently of each other by means of a control signal from the decision unit (7) . The m ultiple blowing nozzles ( 10) can also be controlled independently of each other by a control signal from the decision unit (7) . The multiple ejector fingers (9) and the m ultiple blowing nozzles (10) can be controlled independently of each other by a control signal from the decision unit (7) . The m ultiple ejector fingers (9) and the m ultiple blowing nozzles ( 10) are evenly placed in a transverse direction at the end of the unit (2) for bulk transport of agricultural products. The multiple ejector fingers (9) can be moved to the end of the unit (2) for bulk transport of agricultural products and back. The multiple blowing nozzles (10) are directed towards the end of the unit (2) for bulk transport of agricultural products. This is indicated in Figure 1 with waveforms. A separating plate (11 ) is placed under the end of the unit (2) for bulk transport of agricultural products. When an ejector finger (9) is moved to the end of the unit (2) for bulk transport of agricultural products, a first position of the ejector finger (9) , the ejector finger (9) obstructs a trajectory of an object during a fall from the unit (2) for bulk transport of agricultural products. The ejector finger (9) taps the object and the object falls to the left of the separating plate (1 1 ). The object has been sorted from the bulk flow of agricultural products. If the ejector finger (9) is moved away from the unit (2) for bulk transport of agricultural products, a second position of the ejector finger (9) , the ejector finger (9) does not hinder a trajectory of an agricultural product during a fall from the unit (2) for bulk transport of agricultural products, so that the agricultural product falls to the right of the separating plate () onto a discharge belt (12) and is removed for further processing. I n Figure 1 , the ejector finger (9) is drawn on the left in the first position and on the right in the second position. If a light and / or small object fails at the end of the unit (2) for bulk transport of agricultural products, the object can be blown to the left of the separating plate (11 ) by actuating the blowing nozzle ( 10) . The light and / or small object has been sorted from the bulk flow of agricultural products.

[0105] Figure 2 shows a side view of a sorting device according to a second embodiment of the present invention.

[0106] The sorting device (1 ) in Figure 2 is very similar to the sorting device (1 ) in Figure 1 . The main difference is that the separation unit (8) is placed below- the unit (2) for the bulk transport of agricultural products. I n Figure 2, the ejector finger (9) is drawn on the right in the first position and on the left in the second position. With the ejector finger (9) in the first position, objects during their fall from the unit (2) for bulk transport of agricultural products are tapped by the ejector finger (9) , causing them to fall to the right of the separating plate (1 1 ) onto the discharge belt (12) . The objects have been sorted from the bulk flow of agricultural products. The blowing nozzle (10) is directed away from the unit (2) for bulk transport of agricultural products. If a light and / or small object falls at the end of the unit (2) for bulk transport of agricultural products, by actuating the blowing nozzle (10) the object can be blown to the right of the separating plate ( 11 ) and the object falls onto the discharge belt (12) , The light and / or small object has been sorted from the bulk flow of agricultural products.

[0107] I n this embodiment, the objects are discharged on the discharge belt (12) . It will be apparent to one skilled in the art that a discharge belt can also be placed to the left of the separating plate ( 11 ) , which is used for the removal of agricultural products. This also applies mutatis mutandis to the sorting device (1 ) in Figure 1.

[0108] Figure 3 shows a side view of a sorting device according to a third embodiment of the present invention.

[0109] The sorting device (1 ) is identical to the sorting device (1 ) in Figure 1 , with the only difference being that the sorting device (1 ) comprises multiple auxiliary blowing nozzles (13) . Only a single auxiliary blowing nozzle (13) is visible in Figure 3. The m ultiple auxiliary blowing nozzles (13) are evenly placed in a transverse direction at the end of the unit (2) for bulk transport of agricultural products. The auxiliary blowing nozzles (13) are placed under the unit (2) for bulk transport of agricultural products. The auxiliary blowing nozzles (13) are directed in an opposite direction to the blowing nozzles (10). The directions of the blowing nozzles (10) and the auxiliary blowing nozzles (13) are opposite when projected onto a horizontal plane. The auxiliary blowing nozzles (13) are therefore directed away from the end of the unit (2) for bulk moving of the agricultural products. When actuating the auxiliary blowing nozzles (13) , agricultural products are blown away from the end of the unit (2) for bulk moving of the agricultural products, ensuring that even if the at least one ejector finger (9) has not yet fully returned to the second position, there is only a slight chance that the agricultural products will fall incorrectly to the left of the separating plate (11 ) .

[0110] Figure 4 shows a side view of a sorting device according to a fourth embodiment of the present invention.

[0111] The sorting device ( 1 ) is very sim ilar to the sorting device (1 ) in Figure 1 . The main difference is that the image acquisition unit comprises two cameras (3) , wherein the cameras (3) and the light sources (5) of the image acquisition unit are placed under the end of the unit (2) for bulk transport of agricultural products and wherein the cameras (3) and the light sources (5) are directed towards each other. The agricultural products and the objects between the agricultural products faii down between the cameras (3) and the light sources (5) .

[0112] The numbered elements in the figures are:

[0113] 1 . Sorting device

[0114] 2. Unit for bulk transport of agricultural products

[0115] 3. Camera of image acquisition unit

[0116] 4. I mage processing unit

[0117] 5. Light source of image acquisition unit

[0118] 6. Housing of image acquisition unit

[0119] 7. Decision unit

[0120] 8. Separation unit

[0121] 9. Ejector finger

[0122] 10. Blowing nozzle

[0123] 1 1 . Separating plate

[0124] 12. Discharge unit

[0125] 13. Auxiliary blowing nozzle

Claims

CLAIMS1 . Sorting device for sorting objects from a bulk flow of agricultural products, the sorting device comprising a unit for bulk transport of the agricultural products, a sensor unit for obtaining sensor data from the buik flow for recognizing the objects, a decision unit for generating a control signal for a separation unit based on the sensor data, and the separation unit for separating objects from the bulk flow according to the control signal, characterized in that the separation unit comprises at least one ejector and at least one blowing nozzle, wherein the at least one ejector and the at least one blowing nozzle can be controlled independently of each other by the control signal2. Sorting device according to claim 1 , characterized in that the unit for bulk transport of the agricultural products comprises a conveyor belt or a roller conveyor, wherein the separation unit is placed at an end of the conveyor belt or roller conveyor, wherein the at least one ejector is movable to the end of the conveyor belt or roller conveyor and back and wherein the at least one blowing nozzle is directed towards the end of the conveyor belt or roller conveyor.

3. Sorting device according to claim 1 , characterized in that the unit for bulk transport of the agricultural products comprises a conveyor belt or a roller conveyor, wherein the separation unit is placed under an end of the conveyor belt or roller conveyor, wherein the at least one ejector is movable to the end of the conveyor belt or roller conveyor and back, wherein the at least one blowing nozzle is placed under the end of the conveyor belt or roller conveyor and wherein the at least one blowing nozzle is directed in a direction away from the end of the conveyor belt or roller conveyor.

4. Sorting device according to any one of the preceding claims 1 -3, characterized in that the sorting device comprises at least one auxiliary blowing nozzle, wherein the at least one auxiliary blowing nozzle is directed in an opposite direction to the at least one blowing nozzle.

5. Sorting device according to any one of the preceding claims 1 -4, characterized in that the sorting device comprises multiple ejectors andmultiple blowing nozzles, wherein the m ultiple ejectors and m ultiple blowing nozzles are evenly distributed in a transverse direction at an end of the unit for bulk transport of the agricultural products and wherein there are at least 15 ejectors and at least 20 blowing nozzles per meter6. Sorting device according to any one of the preceding claims 1 -5, characterized in that the blowing nozzles of the sorting device are directed downwards, wherein the blowing nozzles have a blowing direction that makes an angle of at least 15° with a horizontai line.

7. Sorting device according to any one of the preceding claims 1 -6, characterized in that the sensor unit is an image acquisition unit for capturing images of the bulk flow, wherein the sorting device comprises an image processing unit for recognizing the objects in said images, wherein the decision unit is configured to generate the control signal based on the images processed by the image processing unit, and wherein the image processing unit is configured to determ ine a volume of the objects.

8. Sorting device according to claim 7 , characterized in that the decision unit is configured to determ ine a weight of the objects based on a specific weight associated with the objects.

9. Sorting device according to any one of the preceding claims 1 -8, characterized in that the decision unit is configured for carrying out a method according to any one of claims 10-14.

10. Method for sorting objects from a bulk flow of agricultural products, comprising the steps of: supplying the bulk flow of agricultural products on a unit for bulk transport of the agricultural products; obtaining sensor data from the bulk flow using a sensor unit; generating a control signal by a decision unit for separating the objects from the bulk flow based on the sensor data; separating the objects from the bulk flow according to the control signal using a separation unit; characterized in that the separation unit comprises at least one ejector and at least one blowing nozzle, wherein the method comprises the additionalsteps of recognizing the objects on the unit for bulk transport of the agricultural products, wherein, on the basis of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle.1 1 . Method according to ciaim 10, characterized in that the sensor data are images made of the bulk flow using an image acquisition unit, wherein the captured images are processed using an image processing unit, wherein the agricultural products in the bulk fiow are recognized by the image processing unit and wherein the method comprises the additional step of determining a volume of the objects, wherein, based on the recognized objects and the volume of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle.

12. Method according to ciaim 1 1 , characterized m that the method comprises the additional step of determ ining the weight of the objects, wherein the weight is determined based on the determ ined volume and a specific weight associated with the recognized objects, wherein, based on the recognized objects and the weight of the recognized objects, the decision unit generates a control signal for the at least one ejector, or the at least one blowing nozzle, or the at least one ejector and the at least one blowing nozzle.

13. Method according to claim 1 1 or 12, characterized in that the decision unit takes into account a sequence of the objects and the agricultural products on the unit for bulk transport of the agricultural products, and a spacing distance between the objects and the agricultural products when generating the control signal for the separation unit.

14. Method according to claim 13, characterized in that the separation unit comprises at least one auxiliary blowing nozzle, wherein the at least one auxiliary blowing nozzle is directed in an opposite direction to the at least one blowing nozzle and wherein, depending on the sequence of the objects and the agricultural products and depending on a volume or a weight of the objects, the decision unit generates a control signal for the at least one auxiliary blowing nozzle.

15. Use of a sorting device according to any one of ciaims 1 -9 and / or a method according to any one of ciaims 10-14 for sorting contam inated potatoes, carrots, red beets or onions.

Images