Process for the identification of randomly shaped and/or plane materials by determination of the structure of the materials through application of electromagnetic and/or acoustic waves

Abstract: The instant invention relates to the application of electromagnetic waves in the UV-, visible and infrared range and/or of acoustic waves for the identification of randomly shaped and/or plane materials, whereby the materials are irradiated and the structures of the materials are determined, in particular the surface structures of the materials, by identification of the waves, which arrive from the irradiated materials at a receiver-sensor, equipped with a reference dato logger, and comparison of the received data with data of the data logger and whereby a sorting device for sorting out identified materials is operated with the aid of signals arriving from the receiver-sensor.

Description: The instant invention relates to the application of electromagnetic waves in the UV and visible range for the identification of randomly shaped and / or plane materials, whereby the materials are irradiated and the surface fine structures of the materials are determined, by identification with waves of sufficient resolving power, which arrive from the irradiated materials at a receiver-sensor, equipped with a reference data logger, and comparison of the received data with data of the data logger which embrace a sufficient number of surface characteristics of randomly shaped materials and whereby a sorting device for sorting out identified materials is operated with the aid of signals arriving from the receiver-sensor device and that the materials are sufficiently separated by each other Separating and sorting are important processes in industry, trade and household. To date, these procecces are still carried out essentially by manual labor, although modern, fully automatic separating units are known, which are capable of identifying objects on the basis of characteristics, like size, shape, colour, printing, specific marks, like trade marks etc. and which put in operation sorting devices for sorting out identified objects. A well-known example is sorting out of products of inferior quality in the food industry, for example in the case of packaging of coffee-beans and other food and luxury food. Developments of this kind are also known in the field of recycling valuable components from waste. Thus DE-OS 4018 757 discloses sorting of materials by taking advantage of different heat-absorption of electrically conductive and non-conductive waste materials. To this, individualized objects on a conveyer belt are irradiated with infrared radiation, distinct emissions of heat are recorded and by signals from the receiver-sensor a sorting device is put in operation. In DE-OS 4021 882 a process for the identification of individual plastic materials is described. In this process a mixture of different plastics, for example from waste, is irradiated by microwaves, whereby again the individual emission of heat is used for putting in operation a sorting device. For measuring the heat emission, preferably a pyrometer is used. DE-OS 4212 713 discloses a system for recycling containers, which is equipped with a receiver-sensor, which identifies and evaluates among others also surfaces. On page 2 of the specification it is outlined that the characteristic patterns, which are identified like diamond-shaped design, nap-design or grooves on the surface of the containers are such patterns, which have been incorporated already by the producer into the container surfaces. In DE-OS 4125 045 a process for sorting of waste mixtures is disclosed, which is characterized by irradiation of the individual waste objects with electromagnetic and / or acoustic waves, recording of the waves arriving from the irradiated objects by a receiver-sensor for identification of the objects and by passing signals from the receiver-sensor to a sorting device, which sorts out the identified waste objects. The receiver-sensor records informations, like the shape of the object, for example bottle-, beaker-, cup- or tube-shapes and other shapes, as well as printing, product-names, company- and producer-names, trade-marks or colours. DE-OS 4104 501 discloses a process for the automatic identification of plane surfaces of sawn board based on colour changes on the board surface. Hitherto the problem has not been solved, which consists of sorting objects, which possess random and / or plane shapes, and which are not characterized by specific colours, printing etc., for example paper, cardboard, foils or textiles, which may be either unused or waste, furthermore rubble, which may consist of numerous materials, shredder waste, for example from car-shredding and other materials. Applicant has found a non-obvious solution to this problem by a process for the identification of randomly shaped and/or plane materials by irradiating the materials with electromagnetic waves in the UV-, and visible range, characterized in that the surface fine structures of the materials are identified by irradiation of the materials, recording of the waves arriving from the irradiated materials in a receiver-sensor device, which is equipped with a data logger, comparison of the data received, with data stored in the data logger, whereby the data stored, embrace a sufficient number of surface characteristics of randomly shaped materials and in that the materials identified are sorted out by a sorting device which is controlled by signals, received from the receiver-sensor device, and that the materials are sufficiently separated by each other. It is generally known that plane materials possess a surface fine-structure, independent of specific patterns, like diamond-shaped, nap-shaped designs, grooves or other patterns, which have been incorporated already by the producer. Thus cardboard has a surface fine-structur, which is different to the surface fine-structure of glazing paper or type-writer paper. Again a coated paper possesses still another surface fine-structure. Paper in general has a surface fine-structure different to plastic foils. Plastic foils among themselves also exhibit different and characteristic surface fine-structures, which often depend on the type of production unit, but may also depend on the chemical structure of the foil. The instant invention is very well suited for the identification of plane materials like paper, cardboard, foils, textiles and others, independent of the quality of the materials i.e. wether they are new or used, respectively waste materials. A regular outer shape or size of the materials to be identified is of no or only little importance, since a sufficient number of data of randomly shaped materials is available in the data logger for comparison with data obtained from the irrediated objects. Thus the materials may be scrap with random irregular edges. In general also the thickness of the materials is unimportant. Depending on the resolving power of the electromagnetic waves used for the irradiation of the materials, the surface fine-structure is recorded and compared to data stored in the data logger. In this way the identification of specific surfaces and consequently specific materials is possible according to the invention, whereby the identification of the surface fine-structure is sufficient for identification. By specific signals directed to a sorting device, which may be operated pneumatically or mechanically or by other technics, sorting out of the identified materials can be carried out. According to the invention, rubble can be sorted with very good results, since, based on the structure of the material, in particular of the surface fine structure, materials like wood, light weight construction materials, brick material, ceramic material, metals, glass and others can be separated very reliably, even if these materials don't possess a definite shape, but are randomly crushed or broken. The structure of the site of fracture may be of importance according to the instant invention. As a supporting means, for the identification of surface fine-structures of objects, images of the objects obtained by recording the waves, which arrive from the irradiated objects, may be enlarged. As a result, the enlarged characteristic structures can be identified by comparison with structure-data, stored in the data logger. Other marks on the surface of objects, if present, like printings of names, trade marks, colours etc. can be additionally used for identification. UV- and visible light is applied according to the invention. It is of major importance that the materials to be sorted out, are sufficiently individualized respectively separated on the conveyer belt from each other. Receiver-sensors are known to persons skilled in the art. They may be equipped with cameras, video cameras, magnifying devices, sound-sensitive devices and other suitable devices. Radiating devices and sources which emit electromagnetic waves are also known to persons skilled in the art, as well as separating and sorting devices, which may be operated pneumatically, mechanically, hydraulically, electrostatically or in other ways.

Claims: Process for the identification of randomly shaped and/or plane materials by irradiating the materials with electromagnetic waves in the UV-, and visible range, characterized in that the surface fine structures of the materials are identified by irradiation of the materials, recording of the waves arriving from the irradiated materials in a receiver-sensor device, which is equipped with a data logger, comparison of the data received, with data stored in the data logger, whereby the data stored, embrace a sufficient number of surface characteristics of randomly shaped materials and in that the materials identified are sorted out by a sorting device which is controlled by signals, received from the receiver-sensor device, and that the materials are sufficiently separated by each other. Process according to claim 1, characterized in that objects like paper and / or cardboard and / or foils and / or textiles are sorted out from waste mixtures. Process according to claim 1, characterized in that rubble components are sorted out. Process according to claims 1 to 3, characterized in that the identification of the surface fine structures of materials is improved by magnifying the recorded image of the surface-structure and comparison with data stored in the data logger. Process according to claims 1 to 4, characterized in that additional surface-characteristics of materials, like printing and / or marks and / or colours and / or structures incorporated into the surface by the producer are used for identification.

Inventors: KAISER DIETER, WINTRICH FRANZ, KAISER, DIETER, WINTRICH, FRANZ
Applicants: RWE ENTSORGUNG AG, RWE ENTSORGUNG AKTIENGESELLSCHAFT
Application year: 1993
Main classification: B07C5
IPC codes: G01B15, B07C5, G01B17