EP0328126A2 - Method and device for sorting spent glass - Google Patents

Abstract

In order to sort spent glass, fragments with an edge length between 5 and 50 mm are produced by means of a crusher. They are cleaned and divided up into a plurality of fractions according to size by means of a classifier and the fragments with edge lengths below 5 mm are collected as mixed glass. The fragments of each fraction are fed separately from collecting containers (8a to 8c) by means of a conveying device (9) to storage containers (10) in each case, from which the fragments are individually fed to a respective multiplicity of assigned slides (12 and 15 to 17). Colour detection units, preferably light transmitters and receivers measuring for absorption, are provided for detecting the glass colour (colourless, green, brown; non-transparent, non-glass material). As a function of the value of the light transmission, the fragments are fed to predetermined adjacent slides and via the slides directed into assigned sorting containers (18 to 21), sorted according to colours (Fig. 1). <IMAGE>

Description

The invention relates to a method and a device for sorting waste glass.

Waste glass is usually in a mixture of different colored glass. A separation into the different color components is necessary for an economical recycling of the old glass. This applies in particular to colorless waste glass, since even small amounts of colored glass, such as green or brown glass, preclude recycling for the production of objects made of colorless glass. It is also important that when sorting waste glass, the non-glass components such as porcelain, earthenware or ceramic parts are also safely sorted out.

In known methods for sorting waste glass (DE 33 46 129 A1; DE 34 45 428 A1), the waste glass fragments, in particular fragments of hollow glass or also the entire waste hollow glass containers, such as bottles, are separated in the size obtained and by a detection unit conveyed through with a light transmitter and receiver and transferred to sorting containers separately from each other on separate conveyors by means of evaluation electronics. In the known methods, the old glass parts have to be relatively large in order to be reliably detected in terms of their color by the recognition unit. Glass pieces with an edge length of only a few cm cannot be handled with the known methods animals so that these fragments are lost for recycling. However, even larger glass fragments cannot be separated reliably with the known methods, because the fragments are transported in very different positions past the detection unit through the beam path between the light transmitter and receiver, and thus fragments of approximately the same shape and the same color with very different values of the light flow to lead. Flat and upright fragments conveyed parallel to the light rays through the detection unit are often not recognized and are therefore not fed to the correct sorting container. This also applies to curved, larger fragments, which the light rays can pass depending on their position.

Experience has shown that with the previous processes the degree of purity of the colorless waste glass by mixing with stained glass is unsatisfactory and in most cases is not sufficient to use this waste glass for the renewed manufacture of objects from colorless glass.

The invention has for its object to remedy this situation and to develop a method of the type mentioned in such a way that with high utilization of the waste glass obtained a significantly better, i.e. glass of different colors is separated more securely.

• a) Das Altglas wird in Bruchstücke bis auf eine Kan­tenlänge von 5 bis 50 mm zerkleinert,
• b) die Bruchstücke werden der Größe nach in mehrere Frak­tionen unterteilt,
• c) Bruchstücke mit Kantenlängen unter 5 mm werden als Mischglas gesammelt,
• d) die verbleibenden Bruchstücke werden vereinzelt,
• e) die vereinzelten Bruchstücke werden einer Farberken­nungseinheit zugeführt und
• f) die farblich erkannten Bruchstücke werden anschlie­ßend abhängig von der erkannten Farbe zugeordneten Sortierbehältern zugeführt.

To achieve the above object, a method for sorting waste glass is proposed, with the following steps.

• a) The waste glass is broken up into fragments up to an edge length of 5 to 50 mm,
• b) the fragments are divided in size into several fractions,
• c) Fragments with edge lengths below 5 mm are collected as mixed glass,
• d) the remaining fragments are separated,
• e) the separated fragments are fed to a color recognition unit and
• f) the color-recognized fragments are then fed depending on the color assigned to the sorting containers.

In contrast to the known methods, the waste glass parts, such as bottles, glasses and the like, as well as the fragments, are comminuted according to the invention, so that they have a maximum edge length which, in the known methods, is already in the region of the lower limit or below it. This crushing of the old glass parts or fragments creates fragments that are mostly flat and roughly flat and sorted according to their size.

Because these relatively small fragments of the color detection unit are exposed, it is impossible for the largely flat formation of the small fragments that they are not detected, as is possible with hollow glass fragments of larger dimensions depending on the shape and position of the fragment in the area of the detection unit.

Cleaning the fragments before they are fed to the color recognition unit improves the safety of the Continue measuring because adhering dirt or paper residues are removed.

It has proven to be expedient if the fragments are exposed to the action of colored light rays from the light transmitter in order to recognize the color and translucency. This results in greater differences in the light flow in the different colored fragments. Experiments have shown that not only is the separation of the fragments of colorless glass from those of stained glass improved, but the separation effect between fragments of brown and green glass is also improved.

Two different process alternatives have proven their worth. An alternative is that the individual fragments are fed to the color detection unit continuously and unrestrained and pass through them, and that the color detection unit receives an absorption signal during the passage of the fragment and feeds it to evaluation electronics that determine the color of the fragment from the absorption curve.

It is particularly advantageous if only the middle region is used to determine the color of the fragment from the time curve of the absorption curve of a fragment.

The absorption measurement provides a value which, based on an undisturbed normal level achieved in the absence of glass fragments, characterizes the amount of light which does not remain in the waste glass fragment due to absorption or other losses.

The following guidelines are quite informal: Colorless, clear waste glass absorbs light and is recognized as existing, but it absorbs significantly less light than brown or green waste glass. This effect can be enhanced by the selection of certain colored, especially red, light frequencies. In addition, an improved distinction between green and brown glass can be achieved.

The differences in this measuring method are so great that a typical source of error is practically eliminated. So naturally the absorption of a thick glass is normally larger than that of a thin glass.

Due to the crushing of roughly the same size (due to the classification) of essentially flat fragments, however, it is ensured that, as in the case of unfavorably located irregularly shaped bottles, multiple radiation of one and the same glass layer takes place. Even very thick, colorless glass, however, still has a significantly lower absorption value than thin stained glass. This enables a safe separation.

Even lightly tinted glass components that occasionally appear in the old glass can be separated out in this way.

A further improvement occurs through the use of only the average values of the time curve of the absorption curve. This becomes clear when you imagine a piece of glass broken off at the edges. Here, the absorption curve initially decreases only slowly, since due to the extremely small thickness of the glass, only a little light is absorbed by it. In the middle, however, the correct value is determined, while in the end how therefore measurement errors are conceivable. In order to avoid individual errors caused by punctiform holes in the middle of the glass fragment, which occur only relatively rarely, an average value can be taken over this measuring range with the help of evaluation electronics. Instead of the mean value, minimum, maximum or specially directed values can also be taken from the measurement and used for diagnosis and detection.

The second alternative for a method according to the invention is characterized in that the fragments of each fraction for identifying the color and light transmission are exposed individually or several times to light transmitters and receivers which are effective in two different levels and in dependence on the respective mean value of the light flow are fed to the sorting containers via the separate conveyors.

With this method, no continuous measurement is carried out; instead, the broken glass is exposed to effective light transmitters and receivers in a stationary position on two different levels. This also ensures a reliable measured value.

• a) einem Brecher zur Zerkleinerung von Altglas,
• b) einem dem Brecher nachgeordneten Klassierer und Sammelbehältern für mehrere Fraktionen unterschied­lich großer Bruchstücke,
• c) einem Bruchstücksortierer zur Abtrennung von Split­tern und Kleinteilen,
• d) einer Förderrichtung, die von den Sammelbehältern die Bruchstücke der einzelnen Fraktionen zu einer Vereinzelungseinrichtung überführt,
• e) rinnenförmige Rutschen, die von der Vereinzelungs­einrichtung zu einer Farberkennungseinheit führen,
• f) weitere rinnenförmige Rutschen, die von der Farb­erkennungseinheit zu Sortierbehältern führen,
• g) der Farberkennungseinheit nachgeordnete Überfüh­rungseinrichtungen, mit denen in Abhängigkeit von Meßwerten der Farberkennungseinheit die Bruchstücke von der ersten auf eine der weiteren rinnenförmigen Rutschen überführt werden.

To implement the method, a device is proposed with:

• a) a crusher for shredding waste glass,
• b) a classifier downstream of the crusher and collecting containers for several fractions of differently sized fragments,
• c) a fragment sorter for separating fragments and small parts,
• d) a conveying direction which transfers the fragments of the individual fractions from the collecting containers to a separating device,
• e) trough-shaped slides that lead from the separating device to a color recognition unit,
• f) further trough-shaped slides leading from the color recognition unit to sorting containers,
• g) transfer devices arranged downstream of the color detection unit, with which the fragments are transferred from the first to one of the further trough-shaped slides depending on measured values of the color detection unit.

According to the invention, the fragments are fed to the respective color recognition units according to fractions of the different sized fragments on slides.

According to one alternative, their movement on the slides to identify their color is stopped in their movement and then either released on the same slide or transferred to another slide and forwarded to the respective sorting containers for the different types of glass. According to the second alternative, the fragments are not braked, but rather a continuous measurement.

Since the fragments have relatively small dimensions, only slides with correspondingly small dimensions are required. A plurality of slides can thus be connected to the respective storage container without difficulty, so that a high throughput can be achieved by the parallel operation of the slides. Because the fragments due to their heaviness are moved forcefully along the inclined slides, the energy expenditure for conveying the fragments is kept small.

By arranging several storage containers with assigned devices for separating the fragments and subsequent slides, the different fractions of the fragments can be sorted simultaneously and separated into common sorting containers according to the color of the fragments, so that there again fragments of different dimensions but the same glass color to be collected. Non-glass components can be safely separated from the glass fragments due to their opacity and can be collected in a separate container.

In order to separate the fragments coming from the crusher from dirt and paper parts and to improve the recognizability of the color of the fragments, a cleaning device can be provided between the classifier and the crusher, for example a washing device in which the broken material acts on water becomes.

Since the arrangement is usually equipped with a large number of slides and this also results in a corresponding large number of light transmitters and receivers, a significant simplification can be achieved in that all light transmitters are connected to a common light source via glass fiber light guides.

The bottom of the slides is preferably lined with glass, which enables the glass fragments to be moved particularly smoothly and without friction.

A particularly preferred embodiment of the slides is achieved in that the slides each have a U-shaped cross section with a width which corresponds to 1.3 to 1.4 times the maximum edge length of the fragments of the respective fraction, and that light transmitters and receivers are arranged above or below the bottom of the slides.

This prevents jamming of the glass fragments during their sliding movement on the slides. At the same time, it is ensured that the fragments lie flat on the channel bottom and in this position reach the respective color recognition units.

This is an advantage in both alternatives. It is thus prevented that, for example, smaller fragments of glass can pass unnoticed or incorrectly classified at the respective measuring points, in particular the light rays in the chutes.

In devices that work with stopped glass fragments, a particularly favorable design is possible in that the mutually assigned slides are arranged one above the other and have closable and releasable bottom openings by the retainer, the bottom openings being arranged offset from the upper to the lower chute in the conveying direction and the bottom slide is designed as a continuous channel.

It is expedient if the retainers are designed as electromagnetically or pneumatically operable, held in the bottom opening and movable through them and in a pivoting part closing the bottom opening in the plane of the bottom. This is particularly the case when the swivel parts are designed as flaps or swivel wedges with tapering in the conveying direction, and each swivel part is mounted at its end pointing in the conveying direction via a swivel axis on a two-armed lever held between springs acting in opposite directions, on each arm of which an electromagnet acts.

Since the individual fragments or fragments are placed flat on the bottom of the trough-shaped slides by the light transmitter, the possibility of a particularly favorable arrangement of the light transmitter and receiver results from the fact that in a device with retainers in front of each bottom opening of each slide a light transmitter and receivers are arranged normal to the bottom of the slide and a light transmitter and receiver are arranged perpendicularly to it and light passage openings are provided in the region of the central longitudinal line of the bottom and in the side walls of the slide just above the bottom.

In the case of a device with continuous measurement, an arrangement of the light transmitters and receivers is preferred in which one of these two elements is arranged above and below the floor.

The transfer device also has flaps or swivel wedges. However, these do not have the function of the above-mentioned pickup. These are flaps arranged in the bottom of the slide after the evaluation electronics. These only have to be switched back and forth between two positions or functions, namely a continuous position and an open position. In the continuous position, the bottom of the slide is closed by the flap, so that the fragments or fragments are unimpeded can pass through the slide to be fed to a sorting bin. In the open position, the fragments or fragments pass through the bottom of the trough-shaped slide onto another slide underneath. This in turn is equipped with a flap, the position of which can be specified simultaneously by the evaluation electronics. Possibly. the fragments reach a third slide underneath.

The number of slides can be selected depending on how many colors the glass fragments are to be split into. Usually a slide is provided for colorless, green and brown glass and one for ceramics and other non-glass components.

The flaps can be designed as a simplified embodiment of the swivel parts provided in the first alternative.

The drawing shows two exemplary embodiments of the invention in schematic representations.

• Fig. 1 schaubildartig eine Prinzipdarstellung einer Vorrichtung zur Durchführung des Verfahrens gemäß der Erfindung,
• Fig. 2 die Prinzipdarstellung eines Speicherbehäl­ters mit nachgeordneten Sortiereinrichtungen,
• Fig. 3 in vergrößerter Darstellung die Einzelheit A der Anordnung nach Fig. 2,
• Fig. 4 eine Schnittdarstellung des Bereiches zwischen Farberkennungseinheit und Sortierbehälter ge­mäß einer zweiten Ausführungsform,
• Fig. 5 in vergrößerter Darstellung die Einzelheit B der Anordnung nach Fig. 4,
• Fig. 6 einen Schnitt längs der Linie D-D in Fig. 5.

Show it:

• 1 is a schematic representation of a principle of an apparatus for performing the method according to the invention,
• 2 shows the basic illustration of a storage container with downstream sorting devices,
• 3 is an enlarged view of the detail A of the arrangement of FIG. 2,
• 4 shows a sectional illustration of the area between the color recognition unit and the sorting container according to a second embodiment,
• 5 is an enlarged view of the detail B of the arrangement of FIG. 4,
• 6 shows a section along line DD in FIG. 5.

According to the overall arrangement according to FIG. 1, the waste glass obtained is fed in the direction of arrow 1 via a funnel 2 to a crusher 3, in which the waste glass is comminuted in such a way that mostly fragments with an edge length of 5 to 50 mm are produced.

The waste glass leaving the crusher 3 reaches a conveyor 4, to which a washing device 5 is assigned, by means of which the broken waste glass located on the conveyor 4 is acted upon by water jets 5a. As a result of the washing process, the paper parts adhering to the fragments and the dust adhering to the fragments are washed off and also smaller pieces of glass are washed away. The water provided with the aforementioned impurities and glass fragments is passed over a separating or separating device not shown in the drawing, so that the water freed from the impurities and splinters can be fed to the washing device 5 again.

Instead of such a washing device 5, other cleaning devices that work, for example, with air or sandblasting would also be conceivable.

Via the discharge end of the conveyor 4, the fragments remaining and washed on the conveyor reach a classifier 6, which is designed as a screen classifier and through which the supplied glass fragments are sorted into several fractions of different sizes. The fragments with an edge length get out of the classifier half of 5 mm in the collecting container 7, from which they can be removed as a mixing glass for further processing.

Sorted fragments with edge lengths of 5 to 50 mm are collected separately in the remaining collecting containers 8a to 8c, so that three fractions of different sized fragments are obtained, with differently colored glass fragments as well as porcelain, clay and ceramic fragments being mixed .

The individual fractions from the collecting containers 8a to 8c are now transferred separately to a conveyor device 9, only one of which is shown in FIG. 1. In practice, each collecting container 8a to 8c is assigned such a conveying device 9, via which the glass fragments reaching this conveying device are transferred into a storage container 10.

Each storage container 10 is equipped with a device for separating the glass fragments fed to it. 1 shows such a separating device 11 in the form of a slide connected to the storage container 10. The separation of the fragments can take place, for example, in that the storage container 10 is designed as a vibrating vibration container with correspondingly installed baffles, which ensure that the glass fragments reach the slide 11 designed as a separation device and are then separated on the slide. From the separating device 11 in the form of the slide, the glass fragments reach a first inclined, channel-shaped slide 12, which in the example shown has two Holders 13 and 13a which can be transferred into the movement path of the fragments are equipped. Detection units 14 and 14a, respectively, are arranged directly upstream of the hold-ups 13 and 13a in two levels, each detection unit consisting of light transmitters and receivers which are each active in two different levels. The detection units 14 and 14a are connected to evaluation electronics (not shown in FIG. 1) and central control devices for the individual detectors 13 and 13a.

Each of the glass fragments fed to the trough-shaped chute 12 first reaches the pick-up 13 on its conveying path and is exposed there to the light beams of the two light transmitters which are effective in two planes in the rest position. The value of the light flow is measured in the evaluation electronics and, depending on this, the holder 13 is either actuated so that the fragment is released for further movement on the conveyor trough 12 or is transferred from the conveyor trough 12 to a further conveyor trough 15 arranged downstream. When the glass fragment is released for further movement on the conveyor trough 12, the process already described in connection with the retainer 13 is repeated in front of the retainer 13a. The glass fragment is then either released by the retainer 13a either for further conveyance on the conveying trough 12 or transferred to the next conveying trough 15. Approved. The arrangement of the two retainers 13 and 13a in the course of the conveyor trough 12 is provided only for safety reasons in order to check the light transmittance measured by the detection unit 14 again by the detection unit 14a.

In the example it is assumed that only those fragments which consist of colorless glass are transported on the chute 12. These fragments are thus collected in the sorting container 18.

Fragments of glass made of colored glass and fragments made of other non-translucent material are transferred to the next slide 15 via the retainers 13 and 13a. You get on the slide 15 again in front of the support 13, 13a of this slide, only glass fragments of brown glass being conveyed on this slide, for example, in order to get into the sorting container 19. The glass fragments not made of brown glass are transferred to the slide 16 via the retainers 13 and 13a of the slide 15, on which fragments of green glass are released for further conveyance into the sorting container 20 by means of the retainers 13, 13a assigned to this slide. The fragments which are not made of green glass pass in the manner already described through the supports 13 and 13a assigned to the chute 16 onto the chute 17 and via this chute into the sorting container 21. Accordingly, non-transparent fragments, such as fragments of porcelain, Clay or other ceramics are transferred as well as those pieces of glass that cannot be clearly identified as colorless or brown or green fragments, for example, by paper or dirt parts still adhering.

The slides 12 and 15 to 17 described and the sorting containers 18 to 21 assigned to them can be arranged in a plurality, for example in the form of a ring or in series, around the storage container 10, with several of the slides 12 assigned to one another and 15 to 17 can transfer the fragments into the same collection containers 18 to 21. The number of arrangements consisting of the chutes 12 and 15 to 17 per storage container thus determines the sorting capacity.

The double arrangement of the retainers 13 and 13a for each slide with the respectively assigned recognition unit 14 to 14a described in the illustrated example can be reduced to one retainer with an associated recognition unit.

Since the glass fragments to be sorted have only a small edge length between 5 and 50 mm, the chutes 12 and 15 to 17 can be kept relatively narrow. They expediently have a U-shaped cross section with a width which corresponds to 1.3 to 1.4 times the maximum edge length of the fragments of the respective fraction. This prevents jamming of the fragments on the one hand, but on the other hand ensures that the fragments come to rest in front of the hold-ups 13 and 13a in the light beams of the light transmitters of the detection units 14 and 14a, which are effective in two planes, and there in their rest position by determining the light flow can be identified. Since the length of the trough-shaped slides 12 or 15 to 17 can be measured relatively short - in practice the slide 12 is about 1 m long, while the slides 15 to 17 can be kept much shorter - despite the multiple arrangement of the slides, there is none large amount of material is required.

2 gives an enlarged view of the actual one already described in connection with FIG. 1

Sorting device again, wherein in this illustration two of the slides 12 and 15 to 17, which are assigned to one another on the circumference in each case, are shown on the storage container 10.

In Fig. 2, the reference numerals used in Fig. 1 are used for the same parts.

In the illustration according to FIG. 2, two devices designed as vibrating troughs 11a for separating the fragments emerging from the storage container, for example a gap located in the bottom area, are shown below the storage container 10. The storage container 10 can in turn be designed as a vibration container, so that in the area of its bottom the glass shards emerge through an exit gap located there and are separated on the vibration conveyors 11a and fed to the respective slides 12 via controlled flaps or retainers, as already mentioned in connection with Fig. 1 has been described.

2 shows the evaluation electronics and central control device 22, which is connected both to the detection units 14 and 14a and to the pick-ups 13 and 13a.

From detail A of FIG. 2, which is shown in FIG. 3, it can be seen that the retainers 13 and 13a are designed as magnetically actuatable swivel parts and that in the bottom of the channel 12 and also the other channels 15 to 17 bottom openings 23 corresponding to the retainers 13 and 13a are provided. The trained as swivel parts holder 13 can assume three different positions, of which the stop position is shown in solid lines in FIG. 3. In the dash-dotted position 24, the retainer 13 closes the bottom opening 23 of the channel 12 in the plane of the floor, while in the position 25 moved through the bottom opening 23, the retainer 13 releases the bottom opening 23, so that one before in the hold position of the retainer 13 this lying fragment falls through the bottom opening 23 of the chute 12 onto the next channel and arrives in front of the next pick-up 13 assigned to this channel.

To actuate the retainers 13 and 13a, the retainers 13 and 13a, each designed as pivoting parts, are connected in a rotationally secure manner at their end pointing in the conveying direction of the glass fragments to a two-armed lever 26, which in turn is mounted in a stationary manner in the pivot axis 27. The two-armed lever 26 is held in the example between oppositely acting springs 28 and 29 and is connected at the end of its two arms to an electromagnet 30 and 31, which has one end as well as the ends of the springs 28 and 29 are held in a stationary U-shaped component 32.

By actuating the electromagnets 30 and 31, the retainer 13 is transferred to the different positions and, after being released by the respective magnet, is returned via the springs 28 and 29 to the hold-open position drawn out in FIG. 3.

3 also shows the design of the recognition units 14 and 14a more clearly. In the picture In each example, a light transmitter 33 and 34 is arranged perpendicular to the bottom of the chute 12 and the other light transmitter 35 and the associated light receiver are perpendicular thereto. The light transmitter 35 and the light receiver assigned to it are provided just above the bottom of the chute 12, so that the light rays of the light transmitter 35 pass across the fragment lying at rest in front of the holder 13, while the rays emitted by the light transmitter 33 pass onto the Hit the flat side of the respective fragment. Due to the small size of the fragments as a result of the previous comminution and the guidance of these fragments in the channels 12 or 15 to 17, it can practically not happen that the fragments located in front of the pick-ups are not detected by the light beams of the detection units.

For the passage of the light through the wall of the trough 12 or the bottom of the trough, passage openings 36 and 37 are provided in the wall or the bottom, which are translucent closed.

The electrical lines of the magnets 30 and 31 as well as the light transmitters and receivers 33 to 35 are connected to the electronics and central control unit 22 shown in FIG. 3 via the lines indicated in FIG. 3.

The embodiment shown in FIG. 3 and described above applies to all detectors 13 and 13a and detection units 14 and 14a of the slides 12 and 15 and 16, respectively.

To supply all light transmitters 33 and 35, they can be connected to a common one via glass fiber light guides

Light source must be connected. All light guides can be exposed to colored light. However, it is also possible to partially convert the light emerging from the light guides into colored light only there. Experience has shown that increased security of separation of the glass fragments according to their colors can be achieved for all detection units by using red light.

Instead of the individual sorting containers 18 to 21, with circular arrangement of the chutes 12 and 15 to 17 around a storage container 10, collecting troughs of an annular type can also be provided with corresponding discharge devices.

The described retainers 13 and 13a can instead of pivoting parts held in the bottom openings of the respective slides also be provided as side wall sections of the slides which can be pivoted in the manner of a switch, in which case the next following slide must then be arranged laterally next to the previous slide.

Before the waste glass is fed to the crusher 3, it is expediently passed over a classifier similar to the classifier 6 shown and described in FIG. 1, in order to prevent small fragments with an edge length of less than 5 mm and fragments with an edge length of 5 to 50 mm Separate the feeder to the crusher from the remaining fragments and thereby sort the fragments with edge lengths of 5 to 50 mm in the same way as was described in connection with the classifier 6. In this way, only those fragments are fed to the crusher 3 that have an edge length greater than 50 mm exhibit. The fragments of the desired edge length for sorting contained in the waste glass are thus obtained directly from the waste glass without being passed through the crusher. In this way, the proportion of small fragments that cannot be sorted is avoided and the crusher is considerably relieved.

The embodiment shown in FIG. 4 relates to a second alternative for a device according to the invention. Not shown in FIG. 4 is the part which corresponds to FIG. 1 and carries out the initial treatment of the waste glass with crusher 3, conveyor 4, cleaning or washing device 5, collecting containers 7 and 8a to 8c and conveyor device 9.

The glass fragments of a certain fraction of approximately the same size are fed via the chute 12 shown at the top left in FIG. 4. The bottom of the slide 12 is lined with glass, which reduces the friction of the glass fragments. To separate the fragments, the chute 12 can be vibrated. In addition, baffles (not shown) are provided, which possibly also transfer individual, still standing glass fragments into a flat position. The glass fragments can be further separated by thresholds.

A light transmitter 33 and a light receiver 34 are provided in the region of the lower end of the slide 12. The light transmitter 33 is located above the slide 12, the light receiver 34 below the bottom of the slide 12. A reverse arrangement of the elements 33, 34 is also possible. The two elements are adjusted to one another so that the radiation emitted by the light transmitter 33 in the case of an undisturbed radiation pattern

Light rays hit the light receiver 34. Since the bottom of the slide 12 is made of glass, preferably colorless glass, such a beam path is readily possible.

A piece of glass sliding on the chute 12 passes the light beam emitted by the light transmitter 33 due to the predetermined dimensions, a certain proportion of the light being absorbed in the piece of glass.

This measurement does not affect the sliding process of the glass fragment. The light receiver outputs a signal corresponding to the quantity of light received to an electronic evaluation unit 22. This thus receives a continuous chronological sequence via the absorption taking place in the chute 12. As long as no glass fragment slides between light transmitter 33 and light receiver 34, a constant, undisturbed normal level is received. This value is not disturbed by the glass bottom of the chute 12 since it has a constant absorption value over the entire time.

If a piece of glass or a ceramic part, porcelain piece or other foreign body now gets between light transmitter 33 and light receiver 34, the emitted light is absorbed. The extent of this absorption essentially depends on the color properties of the passing fragment. With colorless, so-called transparent glass fragments, there is only a slight absorption, with stained glass a stronger absorption and with foreign bodies a practically complete absorption of the light.

After passing the light transmitter 33 and light receiver 34, that is to say the color recognition unit 14, reach the fragments reach the end of the chute 12 and reach a further no longer vibrating chute or channel 15. This chute 15 and further chutes 16, 17 and 17b arranged underneath lead to sorting or collecting containers 18 to 21. These containers 18 to 21 can 4, in turn, are channels or slides which run perpendicular to the plane of the drawing in FIG. 4, thereby taking up the glass fragments falling from further channels and slides 15 to 17b and finally ending in larger collecting containers. For the sake of simplicity, only cross sections of these elements 18 to 21 are shown.

The course of the slide 15 is equipped with a transfer device, which is formed here by a swivel part 40. The pivoting part 40 is controlled by the evaluation electronics 20 in its movement sequence. Depending on the absorption value, the swivel part 40 can assume two positions. On the one hand, the fragments falling on the slide 15 can allow unhindered passage into the sorting container 18. In this case, the swivel part 40 assumes the position shown in solid line in FIG. 4. This position can be seen more precisely in FIG. 5.

The second possible position is shown in dashed lines in FIG. 4 and causes fragments sliding along the slide 15 to fall through the opening formed onto the next slide 16.

This slide has a comparable structure and in turn has a swivel part 41 which can be controlled by the evaluation electronics 2 2 in two positions. In the position shown in dashed lines, the glass fragment continues to fall onto the third slide 17, which is just if so constructed and ultimately has a pivoting part 42 with which the fragments can reach the chute 17b and thus the sorting container 21.

The evaluation electronics 22 can work, for example, in such a way that colorless glass passes undisturbed via the chute 15 into the container 18, while brown glass via the chute 16 into the container 19, green glass via the chute 17 into the container 20 and foreign parts, such as ceramic, get into the container 21 via the chute 17b.

If the evaluation electronics 22 detects with such a setting that a colorless glass fragment has passed the light transmitter 33 or the light receiver 34, it controls the pivoting part 40 in such a way that the bottom opening 23 of the slide 15 is closed and the glass fragment reaches the container 18 unhindered can.

If it detects a stained glass or ceramic part instead, it ensures that the swivel parts 40, 41 and, if necessary, 42 are appropriately positioned in order to transfer the fragments into the intended container

The control can be carried out in such a way that a switch only takes place when the swivel parts 40, 41, 42 need to be changed. This extends the service life of the drives connected to the swivel parts 40, 41, 42 compared to a respective return to a normal position.

In the example described above, only then must the pivoting part 40 be switched to its open position Position if a fragment that is not identified as a colorless glass appears. As long as only colorless glass fragments are recognized by the evaluation electronics 22, the position of the swivel parts 41 and 42 is irrelevant and a change in position is therefore unnecessary.

The control of the swivel parts 40, 41, 42 can also be set such that, in the event of defects in the drives, a predetermined position of the swivel parts is carried out in such a way that an enrichment of the container for colorless glass with stained glass or foreign parts is avoided in any case. As a result, the quality of the colorless glass is kept constant even in the event of defects. In this case, feeding colorless glass into a stained glass container leads to a lower yield of colorless glass, but is less important for the quality of the stained glass.

5 and 6 details are shown again. The swivel part 40 is connected at its end lying in the conveying direction of the glass fragments in a rotationally secure manner to a two-armed lever 43, which in turn is mounted in a stationary manner in the swivel axis 44. The two-armed lever 43 is connected to an electromagnet 44 as a drive.

In Fig. 6 it can be seen that the slide 15 is covered with glass on its bottom and on the side walls. The glass layers 48 consist of flat glass. The slides 12, 16, 17 and 17b have a similar structure.

Instead of the swivel parts 40, 41, 42, a construction would also be conceivable which transfers the glass fragments from a predetermined path to other paths via air nozzles with a beam which is adjustable in strength and influenced by the measurement.

Claims (19)

1. Procedure for sorting waste glass with the following steps: a) The waste glass is broken up into fragments up to an edge length of 5 to 50 mm, b) the fragments are divided in size into several fractions, c) Fragments with edge lengths below 5 mm are collected as mixed glass, d) the remaining fragments are separated, e) the isolated fragments are fed to a color recognition unit and f) the color-recognized fragments are then fed depending on the color assigned to the sorting containers. 2. The method according to claim 1, characterized in that the isolated fragments of the color detection unit are fed continuously and unchecked and pass through them, and that the color detection unit records an absorption signal during the passage of the fragment and supplies evaluation electronics which determine the color from the absorption curve of the fragment. 3. The method according to claim 2, characterized in that from the time course of the absorption curve of a fragment only the middle area is used to determine the color of the fragment. 4. The method according to claim 1, characterized in that the fragments of each fraction to detect the color and light transmission individually in a resting position one or more times each in two different levels effective light transmitters and receivers exposed and depending on the respective mean value of the light flow over the separate conveyors are fed to the sorting containers. 5. The method according to any one of the preceding claims, characterized in that the fragments to detect the color of the action of colored, in particular red light rays are exposed. 6. The method according to any one of the preceding claims, characterized in that the fragments are cleaned before being fed to the color recognition unit, in particular before being divided into several functions. 7. Device for carrying out the method according to one of the preceding claims with: a) a crusher (3) for crushing waste glass, b) a classifier (6) arranged downstream of the crusher (3) and collecting containers (7 and 8a to 8c) for several fractions of fragments of different sizes, c) a fragment sorter for separating fragments and small parts, d) a conveyor device (9) which transfers the fragments of the individual fractions from the collecting containers (7 and 8a to 8c) to a separating device (11). e) trough-shaped slides (12) leading from the separating device (11) to a color recognition unit, f) further trough-shaped slides (15 to 17) leading from the color recognition unit to sorting containers (18 to 21), g) transfer devices arranged downstream of the color detection unit, with which the fragments are transferred from the first (12) to one of the further channel-shaped chutes (15 to 17) depending on the measured values of the color detection unit. 8. The device according to claim 7, characterized in that the color detection units each have at least one light transmitter and receiver for in particular red light. 9. The device according to claim 8, characterized in that all light transmitters (33, 35) are connected to a common light source via glass fiber light guides. 10. Device according to one of claims 7 to 9, characterized in that a cleaning device (5) is provided between the crusher (3) and the classifier (6). 11. Device according to one of claims 8 to 10, characterized in that the slides (12; 15 to 17) each have a U-shaped cross section with a width which is 1.3 to 1.4 times the maximum edge length of the fragments corresponds to the respective fraction, and that light transmitters and receivers (33 to 35) are arranged above or below the bottom of the slides (12; 15 to 17). 12. Device according to one of claims 7 to 11, characterized in that the bottom of the chutes (12; 15 to 17) consists of glass. 13. The device according to one of claims 7 to 12, characterized in that the slides (12, 15 to 17) in the movement path of the fragments transferable retainers (13, 13a) and in the conveying direction of these upstream, in two planes effective light emitters and - have receiver (14 or 33 to 35) and a device for releasing or transferring the fragments to another channel-shaped slide. 14. Device according to one of claims 7 to 13, characterized in that of the collecting containers (7 and 8a to 8c), the conveyor (9) first to at least one storage container (10) for the transfer of the fragments of the individual fractions, that the or the separating device (11) is assigned to each storage container, such that each separating device (11) assigned to the storage container (10) is connected to a plurality of slides, and that each rod emanating from the separating device cal (12) further slides (15 to 17) of the same design are assigned to which the individual fragments can be transferred one after the other. 15. The apparatus according to claim 13 and 14, characterized in that the mutually assigned slides are arranged one above the other and by the retainer (13; 13a) closable and releasable bottom openings (23), the bottom openings from the upper to the lower slide in the conveying direction are arranged offset and the bottom slide (17) is designed as a continuous channel. 16. The apparatus according to claim 15, characterized in that the retainers (13, 13a) are designed as electromagnetically or pneumatically operable, held in the bottom opening (23) and movable therethrough and in a pivoting part closing the bottom opening in the plane of the bottom. 17. The apparatus according to claim 16, characterized in that the pivoting parts are designed as flaps or pivoting wedges with tapering in the conveying direction, and that each pivoting part at its end pointing in the conveying direction via a pivot axis (27) on a two-armed, between oppositely acting springs ( 28,29) held lever (26) is mounted, on the two arms of which an electromagnet (30,31) acts. 18. Device according to one of claims 13 to 17, characterized in that before each bottom opening voltage (23) of each slide (12; 15; 16) a light transmitter and receiver (33; 34) normal to the bottom of the slide and a light transmitter (35) and receiver arranged perpendicular to it and in the area of the central longitudinal line of the floor and in light passage openings (36, 37) are provided in the side walls of the slide just above the floor. 19. Device according to one of claims 8 to 18, characterized in that the light receiver (34) is connected to an evaluation electronics (22), to which it continuously emits a signal characterizing the received light intensity, and that the evaluation electronics (22) with the Transfer device is connected and this feeds a control signal depending on the signal.

Images