DE212017000206U1 - Device for detecting objects in a material stream - Google Patents

Abstract

Device for detecting objects (9) in a flow of material, comprising at least
a light source (4, 5) for emitting light in a first transmission wavelength range and in a second transmission wavelength range, which is different from the first transmission wavelength range, to the material flow,
a first detector (1) for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the first transmission wavelength range, in a first detection wavelength range,
a second detector (2), which is different from the first detector (1), for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the second transmission wavelength range, in a second detection wavelength range, characterized
in that the first detector (1) is connected to the light source (4) for controlling the light intensity of the first transmission wavelength range, the connection being designed to reduce the light intensity so that it is sufficient for the first detector (1), and / or the second detector (2) with the light source (5) for controlling the light intensity of the second transmission wavelength range wherein the connection is designed to reduce the light intensity so that it is sufficient for the second detector (2),
- That an evaluation device (11) is provided for evaluating the signals of the first and second detectors (1,2) and for determining at least one property of the detected objects (9), wherein the evaluation device (11) with a discharge device (12) for sorting connected by objects (9) from the material flow depending on their properties, and
- That the first detector (1) with the first light source (4) and / or the second detector (2) with the second light source (5) via the evaluation device (11) is connected, wherein the evaluation device (11) is adapted to Just set the intensity of the light sources (4,5) just enough to allow an evaluation of the data of the detectors (1,2).

Description

FIELD OF THE INVENTION

• - eine Lichtquelle zum Aussenden von Licht in einem ersten Sende-Wellenlängenbereich und in einem zweiten Sende-Wellenlängenbereich, der vom ersten Sende-Wellenlängenbereich unterschiedlich ist, auf den Materialstrom,
• - einen ersten Detektor zum Detektieren von Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte, hervorgerufen durch Licht im ersten Sende-Wellenlängenbereich, in einem ersten Detektions-Wellenlängenbereich,
• - einen zweiten Detektor zum Detektieren von Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte, hervorgerufen durch Licht im zweiten Sende-Wellenlängenbereich, in einem zweiten Detektions-Wellenlängenbereich.

The invention relates to a device for detecting objects in a material flow, comprising at least

• a light source for emitting light in a first transmission wavelength range and in a second transmission wavelength range, which is different from the first transmission wavelength range, to the material flow,
• a first detector for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the first transmission wavelength range, in a first detection wavelength range,
• - A second detector for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the second transmission wavelength range, in a second detection wavelength range.

First and second transmit wavelength ranges are different in the sense that they are not identical, but can basically overlap. Also, first and second detection wavelength ranges are different in the sense that they are not identical, but they will usually not overlap.

The device is e.g. suitable for detecting waste glass in the form of cullet, if this is to be separated by color and / or for detecting other impurities, such as stones, metals or plastics, if they are to be removed from the waste glass. The device is also suitable for detecting various plastics or articles or pieces of plastic and then separating them from one another.

The invention, due to the need for two different detectors, does not relate to devices where light is emitted from one or more light sources in two or more transmit wavelength ranges, but the light of all transmit wavelength ranges is detected collectively in a detector. This is about in the US 7339660 B1 the case where the light from light-emitting diode rows 204 . 206 with different color in a common detector 400 is detected. Also the EP 2589858 A1 falls into this category where light of different wavelength from different light sources 10 . 20 . 30 is bundled into a common light beam which is used for the illumination of an object, wherein an image of the object in an imaging device, ie a single detector, is generated.

STATE OF THE ART

To detect objects, two different types of light are often used to produce different properties, e.g. Color and type of material to detect the objects and thus more secure to assign an object to a specific faction. In the case of infrared light as the first type of light or as the first transmission wavelength range and visible light as the second type of light or as the second transmission wavelength range often light sources are used, the two types of light, ie light of both wavelengths, visible and infrared light, send out simultaneously, such as Halogen light sticks. Thus, only one type of light source is needed, which is e.g. facilitates the storage of light sources for replacement.

However, these light sources have the disadvantage that the intensity can only ever be changed jointly for both transmission wavelength ranges. Often, however, only one high intensity is needed for one detection wavelength range or the associated detector, while for the other detection wavelength range or the other detector with a lower intensity, the long run could be found. Now, however, the light source must always be operated at the higher intensity, which can lead to an undesirably high heat development within the device. For example, for a sufficient intensity and color distribution in the visible range, halogen light bars are operated at their respective performance limits. This results in a high proportion of heat radiation within the sorter, in which the light sources and detectors are arranged. This in turn increases the risk of fire in the sorter.

Often, these light sources must be operated with DC voltage to prevent intensity fluctuations by AC.

PRESENTATION OF THE INVENTION

An object of the invention is therefore to provide a detection device which is characterized by a lower heat development, if for a detection wavelength range, a lower intensity than for the other detection wavelength range is sufficient.

• - eine Lichtquelle zum Aussenden von Licht in einem ersten Sende-Wellenlängenbereich und in einem zweiten Sende-Wellenlängenbereich, der vom ersten Sende-Wellenlängenbereich unterschiedlich ist, auf den Materialstrom,
• - einen ersten Detektor zum Detektieren von Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte, hervorgerufen durch Licht im ersten Sende-Wellenlängenbereich, in einem ersten Detektions-Wellenlängenbereich,
• - einen zweiten Detektor zum Detektieren von Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte, hervorgerufen durch Licht im zweiten Sende-Wellenlängenbereich, in einem zweiten Detektions-Wellenlängenbereich.

This object is achieved with a device according to claim 1. The device for detecting objects in a material stream comprises at least

• a light source for emitting light in a first transmission wavelength range and in a second transmission wavelength range, which is different from the first transmission wavelength range, to the material flow,
• - a first detector for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the first transmission wavelength range, in a first detection wavelength range,
• - A second detector for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the second transmission wavelength range, in a second detection wavelength range.

The device is characterized
in that the first detector is connected to the light source for controlling the light intensity of the first transmission wavelength range, and / or the second detector is connected to the light source for controlling the light intensity of the second transmit wavelength range.

The light source thus emits light of a certain first transmission wavelength range, e.g. Infrared light, and a certain second transmission wavelength range, e.g. visible light. The first detector is associated with the light of the first transmission wavelength range and can only detect light caused by the objects due to the light of the first transmission wavelength range. If the reflection light or the transmission light of the objects is detected with the first detector, then the first detection wavelength range of the first detector is at least a partial area of the first transmission wavelength range.

The light of the second transmission wavelength range is different from that of the first transmission wavelength range. That is, the two wavelength ranges are not identical, but an overlapping of the wavelength ranges is possible. If the second transmission wavelength range is e.g. If only visible light is to be included, some infrared light also emits some infrared light, even if it is not detected by the associated second detector.

The second detector is associated with the light of the second transmission wavelength range and can only detect light caused by the objects due to the light of the second transmission wavelength range. If the reflection light or transmission light of the objects is detected with the second detector, then the second detection wavelength range of the second detector is at least a partial area of the second transmission wavelength range.

In the case of fluorescent light of the objects, there is often no overlap of transmission wavelength range (e.g., UV light) and detection wavelength range (e.g., visible light).

The light source can now comprise at least one supercontinuum laser light source which is designed to emit light in a first transmission wavelength range and in a second transmission wavelength range which does not overlap with the first transmission wavelength range.

Supercontinuum or white laser light is laser light which has an extremely broad optical spectrum. While laser light is usually relatively narrow band, a supercontinuum can span more than one octave. Supercontinua can be created by taking advantage of non-linear effects in the transmission of laser beams through glass fibers at high intensities, but also the focus in air is already sufficient. Mostly one uses intense light pulses of femtosecond lasers. But also the use of pulses with much longer durations can show the desired broadening. In long fibers even a continuous laser operation is possible. However, the physical mechanisms involved and the spectral structure of the supercontinuum are quite different depending on the pulse duration, dispersion and length of the fiber, etc. Supercontinuum laser light sources, with each of which light from two different wavelength ranges is introduced into a common beam path, are known in principle from the prior art. For supercontinuum laser light sources, the light intensity in the different wavelength ranges can be set independently. Thus, e.g. the light intensity for infrared light (first transmission wavelength range) is set independently of that for visible light (second transmission wavelength range). As a rule, light of the first transmission wavelength range and of the second transmission wavelength range is emitted at the same time.

• - nur der erste Detektor ist mit der Lichtquelle (z.B. einer Superkontinuum-Laserlichtquelle) zwecks Steuerung der Lichtintensität des ersten Sende-Wellenlängenbereichs verbunden, oder
• - nur der zweite Detektor ist mit der Lichtquelle zwecks Steuerung der Lichtintensität des zweiten Sende-Wellenlängenbereichs verbunden, oder
• - sowohl der erste Detektor ist mit der Lichtquelle zwecks Steuerung der Lichtintensität des ersten Sende-Wellenlängenbereichs verbunden als auch der zweite Detektor ist mit der Lichtquelle zwecks Steuerung der Lichtintensität des zweiten Sende-Wellenlängenbereichs verbunden.

According to the invention, there are basically three possibilities:

• - Only the first detector is connected to the light source (eg, a supercontinuum laser light source) for controlling the light intensity of the first transmission wavelength range, or
• - Only the second detector is connected to the light source for controlling the light intensity of the second transmission wavelength range, or
• - Both the first detector is connected to the light source for controlling the light intensity of the first transmission wavelength range and the second detector is connected to the light source for controlling the light intensity of the second transmission wavelength range.

As a result of the connection between the light source and the detector (s), the light intensity in the first or second transmission wavelength range can always be set so that it is sufficient for the associated detector. For example, an excessive intensity in the first transmission wavelength range can be reduced, so that the heat development by the light source is reduced in this wavelength range. It is therefore conceivable that the detector itself can determine which intensity it requires in the individual transmission wavelength ranges.

• - dass der erste Detektor mit der ersten Lichtquelle zwecks Steuerung der Lichtintensität der ersten Lichtquelle verbunden ist, und/oder der zweite Detektor mit der zweiten Lichtquelle zwecks Steuerung der Lichtintensität der zweiten Lichtquelle verbunden ist. Erste und zweite Lichtquelle können sich dabei im Betrieb der Vorrichtung auf der gleichen Seite des Materialstroms der Objekte befinden, aber auch auf unterschiedlichen Seiten. Unabhängig davon können erste Lichtquelle und erster Detektor im Reflexions- oder im Transmissionsverfahren arbeiten, ebenso können - unabhängig von der Arbeitsweise von erstem Detektor und erster Lichtquelle - zweite Lichtquelle und zweiter Detektor im Reflexions- oder im Transmissionsverfahren arbeiten.

However, as in the case of a supercontinuum laser light source, the light source does not have to have illumination units which can each emit light in both transmission wavelength ranges. Instead, it can also be provided that the light source has both a first light source for emitting light only in the first transmission wavelength range and a second light source for emitting light only in the second transmit wavelength range, and

• - That the first detector is connected to the first light source for controlling the light intensity of the first light source, and / or the second detector is connected to the second light source for controlling the light intensity of the second light source. First and second light source can be located in the operation of the device on the same side of the material flow of the objects, but also on different sides. Independently of this, the first light source and the first detector can work in the reflection or transmission method, likewise - regardless of the mode of operation of the first detector and the first light source - the second light source and the second detector work in the reflection or transmission method.

• - nur der erste Detektor ist mit der ersten Lichtquelle zwecks Steuerung der Lichtintensität der ersten Lichtquelle verbunden, oder
• - nur der zweite Detektor ist mit der zweiten Lichtquelle zwecks Steuerung der Lichtintensität der zweiten Lichtquelle verbunden, oder
• - sowohl der erste Detektor ist mit der ersten Lichtquelle zwecks Steuerung der Lichtintensität der ersten Lichtquelle verbunden als auch der zweite Detektor ist mit der zweiten Lichtquelle zwecks Steuerung der Lichtintensität der zweiten Lichtquelle verbunden.

According to the invention there are three possibilities in the case of a first and a second light source:

• - Only the first detector is connected to the first light source for controlling the light intensity of the first light source, or
• - Only the second detector is connected to the second light source for controlling the light intensity of the second light source, or
• - Both the first detector is connected to the first light source for controlling the light intensity of the first light source and the second detector is connected to the second light source for controlling the light intensity of the second light source.

Due to the connection between the first and second light source and associated detector, the light intensity of the first and second light source can always be set so that it is sufficient for the associated detector. Thus, e.g. Too much intensity of the first light source can be reduced, so that the heat generated by the first light source is reduced. First and second light sources may have their own adjusting devices with which the intensity of the emitted light is adjusted, most simply by changing the current supplied to the respective light source.

It is therefore conceivable that the detector itself can determine which intensity of the first or second light source it requires.

On the other hand, it may also be the case that the quality of the data or images which the detectors detect can only be ascertained during the evaluation of the data or images during the image processing. In this case it can be provided that the first detector and / or the second detector is connected to the light source via an evaluation device which is provided for evaluating the signals of the first and second detectors and for determining at least one property of the detected objects. That is, the evaluation determines whether the light source (s) may need to be set differently, so have to shine about with greater intensity in a transmit wavelength range, so that an error-free evaluation of the data of the detectors is possible. Or the evaluation device determines that the intensity in a transmission wavelength range can be reduced and still the data of the associated detector can be evaluated without errors.

Possible wavelength ranges within the meaning of the invention, both for the light source (s) (transmission wavelength ranges) and for the detectors (detection wavelength ranges), are e.g. visible light, infrared light, UV light, or a portion of said wavelength ranges, e.g. near infrared light (NIR light), or blue light.

For example, it can be provided that the first transmission wavelength range IR light, in particular NIR light, and the second transmission wavelength range includes visible light. In particular, the first transmission wavelength range may comprise only IR light, in particular only NIR light, and the second transmit wavelength range only visible light.

In the event that the light source has both a first light source for emitting light only in the first transmission wavelength range and a second light source for emitting light only in the second transmission wavelength range, the first light source preferably for emitting IR light, in particular NIR light formed. It preferably comprises at least one halogen light source for emitting infrared light, for example a halogen lamp.

The second light source preferably comprises at least one LED light source for emitting visible light.

Of course, the single light source (e.g., the supercontinuum laser light source), the first light source, and the second light source may each be formed of a plurality of similar physical entities, e.g. from a series of multiple units (multiple supercontinuum lasers, LED lamps, halogen lamps, ...) arranged across the material flow, or from several such rows.

If the first transmission wavelength range comprises infrared light, that is to say the first light source emits infrared light, it is provided that the first detector is a detector for infrared light, in particular NIR light. For example, the first detector may comprise a spectrograph for infrared light. The first detector may be sensitive in the case of NIR light in the range of 900-2,300 nm.

If the second transmission wavelength range comprises visible light, that is to say the second light source emits visible light, it is preferably provided that the second detector comprises a camera for visible light. This can be sensitive in the range of 380-750 nm wavelength.

Thus, according to the invention, outgoing light is measured in two different detectors by the same object, in particular also at the same time.

In order to obtain a sorting device for sorting objects in a material flow as a function of at least one of their properties, an embodiment of the invention consists in that an evaluation device is provided for evaluating the signals of the first and second detectors and for determining at least one property of the detected objects. An example of such a sorter is a device for sorting plastic articles or plastic parts, e.g. according to their color.

In this case, the evaluation device is usually connected to a discharge device for sorting out objects from the material flow as a function of their properties. The discharge device may have suction or blowing nozzles, for example, in order to separate a fraction of objects with a specific property from other objects of the material flow. The discharge device is thus also part of the sorter.

An object of the invention is to integrate two different transmission wavelength ranges (e.g., two different illumination units) for a sorter. A transmission wavelength range (eg the second light source) is specifically tailored to the needs of the sensor or detector for visible light, the other transmission wavelength range (eg the first light source) to the needs of the sensor or detector for infrared light, especially for NIR light.

By a separate light source only for infrared light, in particular NIR light, and a separate light source only for visible light, the intensity of the infrared light source can be reduced compared to a common light source for infrared and visible light. This also reduces the red intensity from the infrared light source and the color fidelity in the visible range increases. The same applies to a light source which can serve both detection wavelength ranges and can emit light in two corresponding transmission wavelength ranges, wherein the intensity of the two transmission wavelength ranges can be set independently of one another.

• - eine Lichtquelle auf den Materialstrom Licht in einem ersten Sende-Wellenlängenbereich und in einem zweiten Sende-Wellenlängenbereich aussendet, der vom ersten Sende-Wellenlängenbereich unterschiedlich ist,
• - ein erster Detektor in einem ersten Detektions-Wellenlängenbereich Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte detektiert, das durch Licht im ersten Sende-Wellenlängenbereich hervorgerufen wird,
• - ein zweiter Detektor, der vom ersten Detektor verschieden ist, in einem zweiten Detektions-Wellenlängenbereich Reflexionslicht, Fluoreszenzlicht oder Transmissionslicht der Objekte detektiert, das durch Licht im zweiten Sende-Wellenlängenbereich hervorgerufen wird, und
• - die Lichtintensität des ersten Sende-Wellenlängenbereichs aufgrund einer Verbindung des ersten Detektors mit der Lichtquelle so gesteuert wird, dass die Lichtintensität für den ersten Detektor ausreichend ist, und/oder die Lichtintensität des zweiten Sende-Wellenlängenbereichs aufgrund einer Verbindung des zweiten Detektors mit der Lichtquelle so gesteuert wird, dass die Lichtintensität für den zweiten Detektor ausreichend ist.

A method for operating a device according to the invention may comprise

• a source of light is emitted onto the stream of material light in a first transmission wavelength range and in a second transmission wavelength range that is different from the first transmission wavelength range,
• a first detector detects in a first detection wavelength range reflection light, fluorescent light or transmission light of the objects which is caused by light in the first transmission wavelength range,
• a second detector, which is different from the first detector, detects in a second detection wavelength range reflection light, fluorescent light or transmission light of the objects, which is caused by light in the second transmission wavelength range, and
• - The light intensity of the first transmission wavelength range due to a connection of the first detector with the light source is controlled so that the light intensity is sufficient for the first detector, and / or the light intensity of the second transmission wavelength range due to a connection of the second detector with the light source is controlled so that the light intensity is sufficient for the second detector.

In the following, a possible embodiment of the invention will be described in more detail with reference to the specific application. For the purpose of Color sorting and foreign matter detection can usually be used without contact measurement methods by means of infrared and / or RGB sensors, which on the basis of the registered transmission or absorption of light directed on the material flow a departure of certain materials / objects, such as by distraction in designated fractions by downstream Blow-out or suction nozzles, initiate. The piece goods to be sorted out of the mixed material flow are irradiated on a sorting belt or during a free-fall path by radiation sources and the intensity of the radiation passing through or reflected by the material flow is recorded in its intensity by a detection device according to the invention and compared with reference values. An evaluation device which is in data connection with the detection device subsequently assigns the piece goods to a respective fraction and, in the sense of a control unit, initiates detection of the objects thus identified by sensors or deflection into predetermined containers by means of compressed air or suction nozzles.

The use of visible light or IR light also makes it possible to process the image of an object recorded by means of detectors, which usually contain a CCD camera, by means of image processing and thus also to detect the shape of an object. The detectors have different sensitivities for different wavelengths (ranges). In an RGB camera, e.g. an RGB signal processed, so the colors red, green and blue each transmitted in a separate channel or stored.

The first light source that is used to irradiate the objects can emit light in the infrared range (780 nm -1 mm wavelength), in particular in the NIR range (900 - 2300 nm). The second light source can emit light in the visible range (380-750 nm wavelength). In principle, a UV light source for activating fluorescent light would also be conceivable as the first or second light source, in which case the fluorescent light may again be in the visible range.

In the case of a light source having only one kind of lighting units, e.g. one or more supercontinuum laser light sources, the individual illumination unit would have light in the infrared range (780 nm -1 mm wavelength) in a first transmission wavelength range, in particular in the NIR range (900-2300 nm), as well as in a second transmit wavelength range Emit light in the visible range (380-750 nm wavelength).

list of figures

• 1 ein Sortiergerät mit Detektionsvorrichtung nach dem Stand der Technik,
• 2 ein Sortiergerät mit einer erfindungsgemäßen Detektionsvorrichtung mit erster und zweiter Lichtquelle.

In the following the invention will be described in more detail with reference to the schematic drawings. It shows

• 1 a sorter with detection device according to the prior art,
• 2 a sorter with a detection device according to the invention with first and second light source.

WAYS FOR CARRYING OUT THE INVENTION

1 shows a sorter for sorting objects 9 , For example, plastic waste in the form of colored plastic pieces, according to the prior art. The objects 9 are detected after passing over an inclined plane 10 get into a free fall range, from which a section of the light source 6 lit and from the detectors 1 . 2 is detected. It would also be possible to detect the objects 9 on a conveyor belt. Preference is given to a single-layer material flow.

The objects are (in 1 from the left) with light from the light source 6 irradiated, the light source 6 simultaneously visible light 8th and infrared light 7 sending out. The light source 6 can consist of several similar units that are across the width of the material flow or the inclined plane 10 , ie normal to the drawing plane, are distributed. That of the objects 9 Outgoing reflection light comes with two different detectors 1 . 2 detected, located on the same side of the objects 9 are like the light source 6 ,

The device comprises a first detector 1 for detecting light of a first detection wavelength range, and a second detector 2 for detecting light of a second detection wavelength range different from the first detection wavelength range. That is, first and second detection wavelength ranges are not identical, usually will not overlap, but overlapping is not excluded.

The first detector 1 Here, an IR detector (in particular an NIR detector), for example, includes an objective, a spectrograph and an optical sensor. The second detector 2 is a VIS detector (especially an RGB camera) and includes a lens and an optical sensor. At least one of the detectors can be designed as a line scan camera.

In 1 become the objects 9 from the light source 6 irradiated with light of different wavelengths, namely with infrared light 7 (first transmission wavelength range) and with visible, especially white, light 8th (second transmission wavelength range). That of the objects 9 outgoing reflection light of different wavelength, namely infrared light again 7 and visible light 8th , is from the two different detectors 1 . 2 detected. The light deflecting element 3 , in the beam path to the detectors 1 . 2 is arranged, is partially transparent or wavelength-selective: it reflects infrared light 7 Light, eg the NIR content above 700 nm, and directs it (eg by about 90 °) in the direction of the first detector 1 from. Visible light 8th , eg with wavelengths below 700 nm, is transmitted and passes to the second detector 2 ,

The evaluation device 11 , which is usually designed as a computer, processes the data from the detectors 1 . 2 and determines at least one property (eg, the color) of each object 9 and share the objects 9 then predetermined fractions (eg white - not white) too, so on the basis of this division a separation of the objects 9 can be done. The evaluation device 11 sends a corresponding control signal to the discharge device 12 , eg a blow-out nozzle, so that objects of a fraction (eg the white objects) through the discharge device 12 over a partition 13 Be distracted while objects of the other faction (not white) just will not be distracted and on the other side of the dividing wall 13 stay.

Because usually a high intensity of visible light 8th needed is the light source 6 be operated near their power limit, and thus emits infrared light 7 high-intensity, reflecting the space around the light source 6 heated accordingly, although also a lower intensity of infrared light 7 for the first detector 1 would be sufficient. In the 1 illustrated device of detectors 1 . 2 , Light source 6 and slate plane 10 is usually surrounded by a housing, not shown here, so that the interior of the housing is heated accordingly.

This should now by changing the device as in 2 be remedied shown. 2 differs from 1 in that instead of the light source 6 two different light sources 4 . 5 be provided. The first light source 4 only sends (as far as physically possible, at least mainly) infrared light 7 off while the second light source 5 only (as far as physically possible, at least mainly) visible light 8th sending out. In addition, the two light sources 4 . 5 with the evaluation device 11 connected to the detectors 1 . 2 connected is. The evaluation device 11 can now control signals to control the intensity of the individual light sources 4 . 5 send to them, reducing the intensity of the two light sources 4 . 5 can be adjusted independently of each other. In this case, the evaluation device 11 the intensity of the light sources 4 . 5 so that this is just sufficient to an evaluation of the data of the detectors 1 . 2 to enable. In particular, the intensity of the first light source 4 for infrared light 7 be lowered without the intensity for the second light source 5 for visible light 8th to change. As a result, the heat development of the first light source 4 be lowered.

The first light source 4 is composed of halogen light rods. For certain applications, the light source sends 4 NIR light off, the associated detector 1 is then formed accordingly as an NIR detector. The second light source 5 sits down in 2 composed of several white light LEDs. Every light source 4 . 5 can be influenced by the associated sensor or detector 1,2 independently of the other light source. Since the light intensity in the visible range is generated by the LED illumination, and the NIR sensor of the detector 1 With a lower intensity in the NIR range, the halogen light bars can be operated with a lower power than the specified rated power. This results in a lower electrical operating power and heat radiation, which results in a lower heating of the sorter. A positive side effect is the longer life of the light source 4 , In addition, there is a better color fidelity in the range of visible light by reducing the originating from the halogen lighting red intensity.

Otherwise the device will work after 2 same as those after 1 ,

Basically, first and / or second light source 4 . 5 also work in the transmission process. This could be the first light source 4 here infrared light 7 emits, working in the reflection process, while the second light source 5 here visible light 8th sends out, works in the transmission method, what in comparison to 2 the second light source 5 on the second detector 2 would have to be arranged opposite side of the material flow.

First and second light source 4 . 5 in 2 can be replaced by a light source according to the other embodiment of the invention, the individual illumination units can emit each IR light, especially only NIR light, as well as visible light, the intensity of IR light and visible light can be adjusted separately. This would be accomplished by a supercontinuum laser light source. This would then be (analogous to the first and second light source 4.5 in 2 ) best with both the first and second detectors 1 . 2 connected, for example via the evaluation 11 , Of course, the supercontinuum laser light source with only one of detectors 1 . 2 be connected when the intensity should be adjustable only for one of the two transmission wavelength ranges.

The embodiment with a supercontinuum laser light source is similar to that shown in FIG 1 with the light source 6 , One would have for the subject invention, the light source 6 , such as a Halogenleuchtstab, replaced by the supercontinuum laser light source and this, for example via the evaluation 11 , with one or both detectors 1 . 2 connect.

LIST OF REFERENCE NUMBERS

1

first detector

2

second detector

3

light deflection

4

first light source

5

second light source

6

light source

7

Infrared light

8th

visible light

9

object

10

inclined plane

11

evaluation

12

discharge

13

partition wall

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The 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

• US 7339660 B1 [0004]
• EP 2589858 A1 [0004]

Claims (12)

Device for detecting objects (9) in a material stream, comprising at least - a light source (4, 5) for emitting light in a first transmission wavelength range and in a second transmission wavelength range that is different from the first transmission wavelength range the material flow, - a first detector (1) for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the first transmission wavelength range, in a first detection wavelength range, - a second detector (2), of the first detector (2) 1) is different, for detecting reflection light, fluorescent light or transmission light of the objects, caused by light in the second transmission wavelength range, in a second detection wavelength range, characterized in that - the first detector (1) with the light source (4) for the purpose Controlling the light intensity of the first transmission wavelength range is connected, wherein the connection is designed to reduce the light intensity so that it is sufficient for the first detector (1), and / or the second detector (2) is connected to the light source (5) for controlling the light intensity of the second transmission wavelength range wherein the connection is designed to reduce the light intensity so that it is sufficient for the second detector (2), - that an evaluation device (11) is provided for evaluating the signals of the first and second detector (1,2) and the Determining at least one property of the detected objects (9), wherein the evaluation device (11) is connected to a discharge device (12) for sorting out objects (9) from the material flow as a function of their properties, and - that the first detector (1) with the first light source (4) and / or the second detector (2) with the second light source (5) via the evaluation device (11) is connected, wherein the Auswerteeinrich device (11) is set up to set the intensity of the light sources (4, 5) just enough to allow an evaluation of the data of the detectors (1, 2). Device after Claim 1 , characterized in that the light source (4, 5) comprises at least one supercontinuum laser light source, which is designed to emit light in a first transmission wavelength range and in a second transmission wavelength range, which does not overlap with the first transmission wavelength range. Device after Claim 1 , characterized in that the light source (4,5) both a first light source (4) for emitting light only in the first transmission wavelength range and a second light source (5) for emitting light only in the second transmission wavelength range, and - That the first detector (1) with the first light source (4) for controlling the light intensity of the first light source is connected, and / or the second detector (2) with the second light source (5) for controlling the light intensity of the second light source is connected , Device after Claim 3 , characterized in that the first light source (4) and second light source (5) are in the operation of the device on the same side of the material flow of the objects (9). Device according to one of the preceding claims, characterized in that the first transmission wavelength range IR light (7), in particular NIR light, and the second transmission wavelength range includes visible light (8). Device according to one of Claims 3 to 5 , characterized in that the first light source (4) for emitting IR light (7) is formed. Device according to one of Claims 3 to 6 , characterized in that the first light source (4) is designed to emit NIR light. Device according to one of Claims 3 to 7 , characterized in that the first light source (4) comprises at least one halogen light source. Device after Claim 8 , characterized in that the first light source (4) comprises a halogen flashlight. Device according to one of Claims 3 to 9 , characterized in that the second light source (5) comprises at least one LED light source for emitting visible light (8). Device according to one of the preceding claims, characterized in that the first detector (1) is a detector for infrared light (7), in particular NIR light, and comprises a spectrograph for infrared light (7). Device according to one of the preceding claims, characterized in that the second detector (2) comprises a camera for visible light (8).

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