Device and method for sensory odor detection of objects to be sorted, in particular plastics

Abstract

The invention relates to a device (100; 100a to 100e) for the sensory odor detection of objects (1) to be sorted, in particular plastics, with a conveyor device (10) transporting the objects (1) between a feed area (20) and a discharge area (22) along a conveyor path (34) in a conveying direction (18) by means of a conveyor element, and with a plurality of sensor elements (32) for odor detection of the objects (1).

Description

Technical field

[0001] The invention relates to a device and a method for the sensory detection of odors from objects to be sorted, in particular plastics, which, in connection with the possibility of recycling the objects, is characterized by a particularly advantageous structural design of the device with high quality of the possible sensory detection of odors from the objects or plastics. State of the art

[0002] In the context of plastics recycling, it is desirable to only recycle or use in new products those plastics that are not critical in terms of odors for the respective application. In particular, odors from recycled components that are perceived as unpleasant by users or other people should be avoided.

[0003] EP 3 305 502 A1 discloses a device for monitoring the material properties of plastics, in which plastics are formed or extruded into an endless film strip, the film strip being conveyed along a conveyor device around deflection rollers. Sensor elements are arranged along the conveyor line which, in addition to detecting inclusions or foreign bodies, can also be used to detect sensory properties, in particular odor detection. The relevant sensor elements are arranged stationary in the area of the device. During transport of the film strip, it is guided past the sensor element used for odor detection. With the known device, it is therefore only possible to sensorically detect the odor development of plastics that have already been processed or recycled into the film strip.What would be desirable, however, would be the ability to sort out or separate such plastics prior to any processing, for example to avoid having to undertake the process required for further processing, and in particular the energy required for this. Furthermore, the performance of the known device is limited in that, in order to detect odors as accurately as possible, it is desirable to enable odor detection over a relatively long period of time. However, this is difficult with the known device because the film strip is moved past the stationary sensor element used for odor detection, meaning that only a relatively short period of time is available for odor detection. This is because the device requires a relatively high conveying speed of the film strip to achieve high performance. Disclosure of the invention

[0004] The device according to the invention for the sensory detection of objects to be sorted, in particular plastics, with the features of claim 1 has the advantage that it enables particularly accurate detection of odors from objects or plastics. Furthermore, the device according to the invention makes it possible to very easily sort out or reject objects or plastics that are unsuitable for certain applications because they have an excessive odor before the objects or plastics are subjected to further processing steps.

[0005] The invention is based on the idea of extending the time available for odor detection of objects using a sensor element used for odor detection by transporting or moving the objects along a conveyor line together with the respective sensor elements. This allows the objects to be sensor-detected by one or more sensor elements over a relatively long period of time.

[0006] Against the background of the above explanations, a device according to the invention for the sensory odor detection of objects to be sorted, in particular plastics, with the features of claim 1 therefore has a conveyor device that transports the objects between a feed area and a discharge area along a conveyor path in a conveying direction by means of a conveyor element. Furthermore, a plurality of sensor elements for detecting the odor of the objects are provided, which are movably arranged at least on a partial area of the conveyor path together with the objects that can be conveyed on the conveyor element between the feed area and the discharge area. Finally, it is provided that the signals or measured values of the sensor elements can be fed to a control device.

[0007] In other words, this means that the sensor elements are conveyed along the conveying path of the objects, preferably synchronously or at the same conveying speed. For the purposes of the invention, depending on the specific design of the device, "objects" are understood to mean, in particular, small-sized objects, for example, shredded objects. In the case of plastics, the objects can also be in the form of relatively large plastic bottles or the like, for example, meaning that the objects or plastics have not been previously shredded.

[0008] Advantageous further developments of the device according to the invention for the sensory detection of odors from objects to be sorted, in particular plastics, are listed in the subclaims.

[0009] To enable continuous conveyance of the objects or plastics on the conveyor, the conveyor is preferably designed as a continuously rotating conveyor. Such a continuously rotating conveyor can be designed, for example, as a conveyor arm or, preferably, in the form of a conveyor belt.

[0010] When designed as a conveyor belt, it may also be useful or necessary to have multiple sensor elements arranged perpendicular to the conveyor path to increase performance or adapt the conveyor system to the shape of the object. This makes it possible, for example, to simultaneously detect relatively large objects in several areas or to analyze their odors.

[0011] It is particularly preferred if the conveyor system has receiving spaces for receiving a specific number of objects. These receiving spaces can also be used to easily assign objects that are assessed as negative by the sensors to specific receiving spaces of the conveyor system so that they can then be easily discharged, for example.

[0012] A further qualitatively improved evaluation of the odors is achieved by dividing the receiving spaces into at least essentially closed receiving spaces by means of separating devices, at least during the transport of the objects, and by assigning at least one sensor element to each receiving space. This has the particular advantage that only the objects arranged or located in the receiving space are detected by sensors, and evaporation from objects in neighboring areas of the conveyor system does not distort the measurement results.

[0013] In a structurally preferred embodiment of the last proposal, it can be provided that the separating device has at least one stamping element, that the distance between the conveying element of the conveying device and the at least one stamping element is variable in a direction perpendicular to the conveying direction, and that the stamping element can be positioned at a short distance or in sealing contact with the conveying element of the conveying device or an object transported on the conveying element. The short distance can, for example, be a distance of greater than or equal to 0 cm to less than or equal to 0.5 cm.

[0014] Because the conveyor system typically has a large number of sensor elements, it may be necessary to replace the sensor elements in the event of contamination or failure. For this purpose, the sensor elements are arranged on the conveyor system in an interchangeable manner.

[0015] Alternatively or additionally, it may also be useful to clean the sensor elements using a cleaning device. This can, for example, remove dirt from the sensor surfaces that could distort the measurement results. For this purpose, the sensor elements are designed to be cleanable using a cleaning device that can be controlled by the control unit and is located in the area of the conveyor system.

[0016] Preferably, a unit of the device, in particular the conveyor device for sorting the objects, can be controlled, in particular activated, by means of the control device depending on the signals or measured values generated by the sensor elements. For example, a motor or a robot arm of the conveyor device can be controlled depending on the generated signals or measured values.

[0017] In order to eject in particular the objects that are not suitable for further processing in a particularly simple manner, an ejection device for ejecting objects can be arranged in the discharge area, wherein the ejection device that can be controlled by the control device can be controlled, in particular activated, depending on the signals or measured values generated by the sensor elements.

[0018] Furthermore, the invention also comprises a method for the sensory odor detection of objects to be sorted, in particular plastics, in particular by means of a device according to the invention as described so far, wherein the objects are transported between a feed area and a discharge area along a conveyor path in a conveying direction by means of a conveying element of a conveying device, wherein the odor detection of the objects takes place by means of a plurality of sensor elements which are moved at least on a partial area of the conveyor path together with the objects which can be conveyed on the conveying element between the feed area and the discharge area, wherein the signals or measured values of the sensor elements are fed to a control device, and wherein the control device controls a device, in particular an ejection device for ejecting non-usable objects, as a function of the signals or measured values of the sensor elements.

[0019] In particular, the method is used to detect the odors of plastics using the sensor elements.

[0020] The process also serves to identify objects that are used for the production of products from the objects as part of a recycling process, whereby odors or fumes from the products made from the objects should not be perceived as unpleasant by users or persons. Unpleasant is defined as exceeding limit values for chemical elements and / or their compounds that were previously defined to classify such objects or plastics as unsuitable for the production of products. Such products include, for example, everyday objects, power tools, or products in the automotive sector, particularly in the automotive interior sector, such as trim panels or similar components.

[0021] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawings. Short description of the drawings Fig. 1 shows a schematic representation of a device for sensory odor detection of plastics, Fig. 2 a representation of a strand of a conveyor belt with replaceable sensor elements attached thereto and Fig. 3 to Fig. 7 simplified representations compared to the Fig. 1 modified devices with different arrangements of sensor elements used for odor detection. Embodiment of the invention

[0022] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0023] In the Fig. 1 shows a highly simplified device 100 for sensory odor detection of plastics 1 to be sorted. The plastics 1 are in particular designed as small pieces of plastics 1, for example in the form of shredded plastic particles or as not yet divided plastic parts, e.g. in the form of bottles 2. However, the device 100 is not intended to be limited to plastics 1 to be sorted as objects, but is fundamentally suitable for objects made of a wide variety of materials.

[0024] The device 100 comprises a conveyor device 10, which is designed as an endless conveyor device 10 in the Fig. 1 is designed in the form of a conveyor belt 12 with a strand 13. The strand 13 of the conveyor belt 12 is guided around at least two deflection rollers 14, 16 and is preferably continuously movable in a conveying direction 18 by means of a drive (not shown).

[0025] The plastics 1 are placed or poured onto the top of the run 13 in a feed area 20. In a discharge area 22, the plastics 1 are discharged, depending on the sensory analysis, either into a first container 23 or a second container 24. For example, the first container 23 is used for plastics 1 that can or should be further processed for a specific application, while the second container 24 is used to hold plastics 1 that are not suitable for further processing. For this purpose, the device 10 has an ejection device 25 that sorts the plastics 1 into the containers 24, 26 by means of an air nozzle 26 that can be controlled by a control device 30 of the device 10.

[0026] Sensor elements 32 for sensory odor detection of the plastics 1 are arranged in recesses or on the upper side of the strand 20, preferably at equal distances from one another, wherein in the illustration of the Fig. For the sake of simplicity, sensor elements 32 are shown in Figure 1 only in the area of a conveyor section 34 for the plastics 1 between the feed area 20 and the discharge area 22. In fact, however, the sensor elements 32 are located along the entire length of the run 13.

[0027] The typically identically designed sensor elements 32 are preferably connected interchangeably to the strand 13 or the conveyor belt 12, for example by clipping into openings 36 of the strand 13, as shown schematically in the Fig. 2. The sensor elements 32 may, for example, be gas sensors manufactured and sold by the applicant under the designation "BME688".

[0028] Furthermore, the sensors 32 are connected to the control device 30, for example via Bluetooth or other technologies known per se from the prior art, in order to supply the control device 30 with their signals or measured values as input variables in order to control the discharge device 25 as required. For this purpose, the control device 30 has an algorithm which is designed to detect, depending on the signals or measured values of the sensor elements 32, plastics 1 that are unsuitable for the production of products due to the exceeding of odor-specific limit values. Due to a known position of the respective sensor element 32 on the strand 13, a targeted control of the air nozzle 26 can take place, in particular in conjunction with another sensor device, for example a camera 38.

[0029] It is essential that the sensor elements 32, together with the plastics 1, which are each located in the detection range of the sensor elements 32, are moved along the conveying direction 18 (synchronously) between the feed area 20 and the discharge area 22 along the conveying path 34 of the plastics 1, so that a relatively long period of time is available for the sensory odor detection of the plastics by the sensor elements 32.

[0030] In the Fig. 3 shows a section of a device 100a which has two conveyor belts 12a and 12b arranged parallel to one another, between whose strands 13a, 13b plastic 1, for example in the form of bottles 2, is conveyed in the conveying direction 18. The sensor elements 32 are arranged in recesses 40 of the strands 13a, 13b. The area between the strands 13a, 13b can be divided, for example by means of flaps 45, 46 or similar elements arranged so as to be movable in the direction of the double arrows 42, 43, into at least substantially closed receiving spaces 48 for a specific quantity of plastics 1 or bottles 2. For this purpose, on both sides of the strands 13a, 13b, in parallel to the plane of the drawing Fig. 3 extending planes, there may be stationary side walls (not shown) which are arranged with as little gap as possible to the strands 13a, 13b. Furthermore, based on the Fig. 3 that several sensor elements 32 are provided both above and below the respective receiving space 48, so that an improved detection of odors is enabled.

[0031] The Fig. The device 100b shown in Figure 4 has a conveyor belt 12 with a strand 13 in which recesses 50 are formed to form receiving spaces 54 for plastic 1. A sensor element 32 is arranged at the bottom of each recess 50. Furthermore, a stamp element 58, which is movable in the direction of the double arrow 56 in the direction of the strand 13, is provided as a separating device in order to form receiving spaces 54 that are as tight as possible. Optionally, further sensor elements 32 can be arranged in the stamp element 58, which can temporarily detect odors from the respective receiving space 58 during the conveyance of the plastic 1.

[0032] The Fig. 5 shows a detail of a device 100c for transporting bottles 2 on the run 13c of the conveyor belt 12c, in which a single stamping element 62 is provided for each bottle 2, which stamping element is, for example, attached to a separate run 64 in order to be able to be moved together with the bottle 2 in the conveying direction 18. A sensor element 32 is arranged on the stamping element 62 on the side facing the bottle 2. The stamping element 62 can be positioned against the surface of the bottle 2 in the direction of the double arrow 66 and has, for example, a rubber bellows 68 on the edge, which forms a closed space 70 when in contact with the bottle 2.

[0033] The Fig. The device 100d shown in Figure 6 has a housing 72 with a substantially rectangular cross-section, which surrounds the conveyor belt 12d and the plastic 1 conveyed on the conveyor belt 12d. In the region of an upper wall 74 of the housing 72, a longitudinal slot 76 is formed, in which a sensor element 32 is movably arranged on a carriage 78 or similar element in order to be able to move synchronously with the plastic 1 or the conveyor belt 12.

[0034] Most recently, in the Fig. 7 shows a section of a device 100e whose conveyor belt 12e has, for example, three strands 81 to 83 arranged parallel to one another and connected to one another or movable synchronously. Each strand 81 to 83 has sensor elements 32 arranged at equal distances from one another on its upper side. Central webs 84, 86, preferably movable up and down, are provided between the strands 81 to 83. A bottle 2 as plastic 1 covers all three strands 81 to 83 in a direction perpendicular to the conveying direction 18.

[0035] The device 100, 100a to 100e described so far can be modified or altered in many different ways without deviating from the inventive concept.

[0036] For example, it may be necessary to clean the sensor elements 32 or their sensitive surfaces due to contact with contaminated plastic 1 or similar. For this purpose, for example, a cleaning agent that is only used in the Fig. 1, which can be controlled by the control device 30 and has a rotating brush 92 or similar cleaning element, which is arranged in a stationary manner in the area of the conveyor device 10, for example near the strand 13, below the conveyor section 34. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] EP 3 305 502 A1

[0003]

Claims

[1] Device (100; 100a to 100e) for the sensory odor detection of objects (1) to be sorted, in particular plastics, with a conveyor device (10) which transports the objects (1) between a feed area (20) and a discharge area (22) along a conveyor path (34) in a conveying direction (18) by means of a conveyor element, and with a plurality of sensor elements (32) for detecting the odor of the objects (1), which are movably arranged at least on a partial area of the conveyor path (34) together with the objects (1) which can be conveyed on the conveyor element between the feed area (20) and the discharge area (22), wherein the signals or measured values of the sensor elements (32) can be fed to a control device (30) of the device (100; 100a to 100e). [2] Device according to claim 1, characterized by that the conveyor device (10) is designed as an endlessly circulating conveyor device (10). [3] Device according to claim 2, characterized bythat the conveying device (10) is designed in the form of a conveyor belt (12; 12a to 12e) with at least one strand (13; 13a to 13c; 81 to 83) as a conveying element. [4] Device according to claim 3, characterized by that a plurality of sensor elements (32) are assigned to the at least one strand (81 to 83) in a direction perpendicular to the conveyor line (34). [5] Device according to one of claims 1 to 4, characterized by that the conveying device (10) has receiving spaces (48; 54) for receiving a predetermined quantity of objects (1). [6] Device according to claim 5, characterized by that the receiving spaces (48; 54) can be subdivided by separating devices into at least substantially closed receiving spaces (48; 54) at least during the transport of the objects (1), and that at least one sensor element (32) is assigned to each receiving space (48; 54). [7] Device according to claim 6, characterized bythat the separating device has at least one stamp element (58; 62), that the distance between the conveying element of the conveying device (10) and the at least one stamp element (58; 62) is variable in a direction running perpendicular to the conveying direction (18), and that the stamp element (58; 62) can be positioned at a short distance or in sealing contact with the conveying element of the conveying device (10) or an object (1) transported on the conveying element. [8] Device according to one of claims 1 to 7, characterized by that the sensor elements (32) are arranged interchangeably on the conveyor device (10). [9] Device according to one of claims 1 to 8, characterized bythat a unit (10, 25) of the device, in particular the conveyor device (10) for sorting the objects (1), can be controlled, in particular activated, by means of the control device (30) as a function of the signals or measured values generated by the sensor elements (32). [10] Device according to one of claims 1 to 9, characterized by that an ejection device (25) for ejecting objects (1) is arranged in the discharge area (22), wherein the ejection device (25) which can be controlled by the control device (30) can be controlled, in particular activated, as a function of the signals or measured values generated by the sensor elements (32). [11] Device according to one of claims 1 to 10, characterized by that the sensor elements (32) can be cleaned by means of a cleaning device (90) which can be controlled by the control device (30) and is arranged in the region of the conveyor device (10). [12] Device according to claim 11, characterized bythat the cleaning device (90) has at least one cleaning element, in particular a brush (92), which is designed to clean a sensitive surface of the sensor element (32). [13] Method for the sensory odor detection of objects (1) to be sorted, in particular plastics, by means of a device (100; 100a to 100e), which is designed in particular according to one of claims 1 to 12, characterized bythat the objects (1) are transported between a feed area (20) and a discharge area (22) along a conveying path (34) in a conveying direction (18) by means of a conveying element of a conveying device (10), that the odor detection of the objects (1) takes place by means of a plurality of sensor elements (32) which are moved at least on a partial area of the conveying path (34) together with the objects (1) which can be conveyed on the conveying element between the feed area (20) and the discharge area (22), wherein the signals or measured values of the sensor elements (32) are fed to a control device (30), and wherein the control device (30) controls a device, in particular an ejection device (25) for ejecting non-usable objects (1), as a function of the signals or measured values of the sensor elements (32). [14] Method according to claim 13, characterized bythat the smells of plastics (2) as objects (1) are detected by means of the sensor elements (32). [15] Method according to claim 13 or 14, characterized by that the method serves to detect objects (1) which are used in the context of recycling to produce products from the objects (1), wherein evaporations or odors of the products are not perceived as unpleasant by users or persons.

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