EP0568883B1 - Management system for faults in overlapping formations of printed products - Google Patents

Description

The invention lies in the field of further processing of printed products, in particular printed products in scale formation, and relates to a system consisting of means and functions according to the preamble of the independent patent claim for error management of errors in the scale formation.

Printed products are laid out in shingle formation, for example from rotary presses, from unwinding stations from winding or from feeders from stacks. Print products in scale formation are processed further directly in scale formation or first converted into another transport formation, for example into a conveying stream of print products hanging individually from clamps, and in this form are led to further processing.

Scale streams of printed products contain flaws, for example in the form of defective products, missing products, shifted products or multiple-used locations. Due to these defects For example, defective products, gaps in defined product sequences (e.g. address sequences) or even production interruptions arise during further processing, which must be prevented if possible.

According to the prior art, errors in scale formation are at least partially corrected by connecting further devices between the device producing a scale flow and the device further processing the scale flow, which, independently of the higher-level process, are concerned with eliminating fault points from the scale flow, so that an as error-free shingled stream as possible is available for further processing. Such devices are, for example, scale buffers, by means of which gaps in scale flows can be closed. Such devices are complex and take up space, in particular if the scale flow for the intermediate device also has to be converted. Under no circumstances is such a device capable of eliminating all the fault points that occur, so that several may be necessary for the highest demands. Since the devices mentioned function in isolation, they require their own sensor and control systems, which can be very complex. In particular, they are also not suitable for processing differentiated shingled streams, that is to say shingled streams with, for example, two different, alternating product distances.

It is the object of the invention to create a defect management system, consisting of means and functions, with which defect points in a scale formation of printed products, which are fed to further processing, are processed with optimized effort. The error management system should be able to be optimized in an application-specific manner in such a way that it has an effect with minimal additional equipment prevent defects in the scale formation (regardless of their frequency and type) for further processing or limit it to a tolerable level. The system should be applicable to any type of shingled stream, i.e. it should be independent of the type of overlap (front edge below or above), the orientation of the products (folds at the front or back) and the thickness of the products, and in particular it should be be applicable for differentiated scale flows.

Figur 1

ein Funktionsschema des erfindungsgemässen Fehlermanagement-Systems;

Figur 2

eine beispielhafte Anwendung des erfindungsgemässen Fehlermanagement-Systems;

Figuren 3a bis d

verschiedene Fehlerstellen in einem Schuppenstrom mit den entsprechenden Messsignalen eines beispielhaften Beobachtungselementes.

Figur 4

ein Blockschema für eine beispielhafte Ausführungsform des Interpretationselements;

Figur 5

ein Schema für die Eichung eines Interpretationselements;

Figur 6

ein Blockschema einer beispielhaften Ausführungsform des Steuerelementes;

Figur 7

ein Bedienungspannel für eine beispielhafte Ausführungsform eines kombinierten Interpretations- und Steuerelementes.

Figur 8

Verdrahtung einer beispielhaften Eich- und Fehlerdetektionsfunktion.

This problem is solved by the fault management system according to the independent claim. The system is described using the following figures. Show:

Figure 1

a functional diagram of the fault management system according to the invention;

Figure 2

an exemplary application of the error management system according to the invention;

Figures 3a to d

different fault points in a scale stream with the corresponding measurement signals of an exemplary observation element.

Figure 4

a block diagram for an exemplary embodiment of the interpretation element;

Figure 5

a scheme for the calibration of an interpretation element;

Figure 6

a block diagram of an exemplary embodiment of the control element;

Figure 7

an operating panel for an exemplary embodiment of a combined interpretation and control element.

Figure 8

Wiring of an exemplary calibration and error detection function.

FIG. 1 shows a rough functional diagram of the error management system according to the invention. This has an observation element 1, an interpretation element 2, a control element 3 and at least one controlled element 4.1, 4.2 and 4.3. The observation element 1 is arranged in the region of the scale stream S. The controlled elements 4.1 / 2/3 are elements, if possible, which are used for transport, further processing or conversion into other transport formations and which may be specially equipped, in particular controllable, for their additional function for error processing. They are all arranged downstream of the product flow observation element.

The observation element 1 observes the shingled stream S supplied for further processing and delivers a measurement signal corresponding to the shed stream to the interpretation element 2. The interpretation element 2 compares the measurement signal of the observation element 1 with corresponding setpoints and uses this comparison to detect fault points in the shed stream which, depending on the embodiment, also differ Assigns error types (blank space, defective product, moved product or multiple-occupancy). If the interpretation element detects an error, it generates an error pulse and, depending on the type of error, forwards it to at least one input of the control element 3 assigned to a specific controlled element. The control element 3 generates a control pulse for the controlled element (4.1, 4.2 or 4.3) from the error pulse and delays it this corresponds to the time required for the transport of the fault location from the observation point to the controlled element, such that the reaction of the controlled element caused by the control pulse occurs when the fault location passes its area of effect. The reaction of the controlled element consists in converting a fault location that cannot be directly eliminated into an eliminable one (ejecting faulty or multiple products, which creates an empty space), eliminating an eliminable fault location (closing the blank space) and / or suppressing further processing of the fault location (fault location pass through further processing step without further processing).

For the detection and interpretation of the defects, the interpretation element 2 needs setpoints and tolerance ranges that have to be matched to the product to be processed (e.g. product thickness) and to the scale flow to be processed (e.g. type of overlap, product distance) and saved. Tolerance ranges are also entered and saved or are fixed in the interpretation element. The interpretation element can also be designed to be self-learning.

For the generation of the control pulses and their delay, the control unit requires data about the controlled elements and about the arrangement (in relation to the product flow) of the observation element and the controlled elements (e.g. distance from the area of the observation element to the area of the controlled element in number of cycles necessary for the transport over this route) and data about the products to be processed (e.g. product length). These data are also entered and stored in the control element or are predefined therein.

Additional error impulses can be fed to the control element from a device arranged further upstream of the product, for example messages from the rotary press with regard to waste gaps or printing errors which can lead to defective products. The control element processes such messages in the same way as error signals of the interpretation element, taking into account the distance between the reporting element and the controlled element.

The error management system is subordinate to the same system cycle, to which all transport and further processing elements within the scope of the system must also be subordinate. Therefore, even with a functional connection between, for example, the rotary press and a controlled element of the fault management system, it is a prerequisite that the scale flow between the rotary press and the controlled element is not re-clocked.

The system according to the invention makes it possible, by means of appropriate control of devices which are advantageously also necessary for further processing, to eliminate application-specific errors in the incoming stream of flakes, to convert them and / or to let them run through the further processing in such a way that no or at most tolerable, defective products are produced.

Depending on the application, the embodiments of the observation element, interpretation element, control element and controlled elements can therefore be different, but their functions remain the same.

The faults that can be detected by the fault management system according to the invention are mainly: vacancies in the shingle stream, locations in the shingle stream occupied with an incorrect number of products (positions), locations in the shingle stream occupied with defective products, and products that are positioned so strongly displaced in relation to neighboring products in the conveying direction that they cannot be processed further without correction.

The fault management system according to the invention treats empty spaces, for example by closing them, or by controlling the further processing in such a way that the empty space happens without further processing. It treats areas occupied by a defective product, for example by ejecting the defective product and further processing the resulting empty space in the manner mentioned. For example, it treats multiply occupied positions as if they were occupied by a faulty product or ignores them if they are saved in a subsequent scale buffer. It treats areas with a shifted product, depending on the size of the shift, as a space with an immediately preceding or immediately following multiple-occupied position or ignores it.

FIG. 2 shows an example of an application of the error management system according to the invention. For this application, the observation element 1 and the interpretation element 2 are equipped, for example, in such a way that vacancies, multiple-occupied locations and locations occupied with a defective product can be distinguished. The stream of shingles runs on a conveyor belt 21, in the area of which the observation element 1 is arranged, into the area of the fault management system. It is then taken over by a pre-clocking element 22, on which the products are positioned exactly in the conveying direction by cams engaging the rear edges of the products. Products that are very strongly displaced are removed by the Pre-clock element 22 is converted into multiple-occupied positions and corresponding empty spaces, which is why the error management system need not be set up for the detection of shifted products. From the pre-clocking element 22, the stream of shingles is taken over by a clamp conveyor 23 and transferred by the latter to a clamp buffer 24, which delivers the products to an insertion drum 25. The controlled elements are a switch 10 which separates discharged products into defective and multiple products, a triggering device 20 which acts on the clamps of the clamp transporter 23 so that they can be opened above the switch 10, and a controlled takeover of the products by the clamps of the clip buffer 24 at its input 30.

The triggering app 20 opens the brackets that have taken the wrong number of products (multiple positions) or a faulty product. The switch 10, depending on the position (double arrow W), guides the defective products that have been removed according to arrow F, for example from the process, the products from Multiple positions according to arrow M, for example in a return to the process. The discharge creates empty spaces in the product flow. At the controlled input 30 to the clamp buffer 24, no clamp is transported further if the corresponding clamp of the transporter 23 has no product to transfer (empty space), whereby empty spaces are closed.

The function of the error management system for the application shown in FIG. 2 is now as follows: The shingled stream with defects passes the observation point with the observation element 1. The observation element supplies a measurement signal to the interpretation element 2. The interpretation element generates error signals for those with a fault Product occupied positions (a), for multiple occupied positions (b) and for spaces (c). These error pulses are forwarded to inputs of the control element 3, which are each assigned to one of the controlled elements (10, 20, 30) (d, e, f), namely: for locations (a) occupied with defective product to the input d for positioning the switch 10 to the right in the figure such that the defective product to the left of the switch can be removed from the process according to arrow F, at the input e for the triggering device for opening the clamp which transports the defective product, and on the entrance f for closing the gap created by the removal; for multiple occupied points (b) at the input d for positioning the switch 10 in the figure to the left, such that the products on the right of the switch according to arrow M, for example, can be returned to the process, to the input e for the triggering device Opening the bracket that transports the wrong number of products and to the entrance f to close the gap; for spaces at the exit f to close the gap.

At the outlet 26 of the clip buffer, where the products are introduced, for example, into a plug-in drum 25, a product stream is available which has no defective products, no multiple products and no empty spaces.

The arrangement shown is only one example of an application, of which an infinite number are conceivable. The application shown could also function differently than described: for example, the defective products could also be discharged during the transfer from the pre-clock 22 to the staple transporter 23, so that the triggering device 20 would only have to convert multiple-used positions into empty spaces and the switch 10 would be unnecessary. However, since the clamp control at a transfer point is usually so slow with a movement template it is realized that several clamps each move in different closing states in the area of the template, the effort to control individual clips that should not close in this area would be greater than the control of the triggering device 20. Of course, it would also be possible instead of the one triggering device 20 and switch 10 use two release devices and no switch.

The observation element 2 is generally an element that observes the shingled stream. Observation elements can be assigned to two groups: those that deliver a clocked signal, that is, a signal that delivers a meaningful measurement result once per system cycle, and those that deliver a continuous signal. For example, an observation element can measure the thickness of the entire scale stream or the thickness of each element of the scale stream.

• eine Abtastrolle, deren Ausschlag gegenüber einer Ruhelage (Nullage) als Messsignal erfasst wird und die ein kontinuierliches, mit der Gesamtdicke des Schuppenstromes korreliertes Messsignal liefert;
• eine Vorrichtung gemäss der deutschen Offenlegungsschrift Nr. 3419436 (F160) derselben Anmelderin, die ein getaktetes, mit der Dicke des gesamten Schuppenstromes korreliertes Messsignal liefert;
• eine Vorrichtung gemäss der schweizerischen Patentanmeldung Nr. 510/92 (19.2.92, P0560) derselben Anmelderin, die im wesentlichen ein kontinuierliches, mit den oben auf dem Schuppenstrom liegenden Produktekanten korreliertes Messsignal liefert;
• eine Vorrichtung gemäss der schweizerischen Patentanmeldung Nr. 3231/90 (5.10.90, P0453) derselben Anmelderin, die ein getaktetes, mit der Dicke des jeweils obersten Produktes des Schuppenstromes korreliertes Messsignal liefert.

Devices that measure thickness and can be used as observation elements are, for example:

• a scanning roll, the deflection of which compared to a rest position (zero position) is recorded as a measurement signal and which supplies a continuous measurement signal correlated with the total thickness of the scale flow;
• a device according to German Offenlegungsschrift No. 3419436 (F160) by the same applicant, which provides a clocked measurement signal correlated with the thickness of the entire scale flow;
• a device according to Swiss patent application No. 510/92 (February 19, 1992, P0560) by the same applicant, which essentially provides a continuous measurement signal correlated with the product edges lying on the scale stream;
• a device according to the Swiss patent application No. 3231/90 (5.10.90, P0453) by the same applicant, which a clocked with provides the measurement signal correlated with the thickness of the uppermost product of the shingled stream.

Devices other than observation element 1 can also be used, for example sensor arrangements with which the distance between the shingled stream and a fixed reference point is measured in a contactless manner, sensor arrangements with which patterns on the top of the shingled stream are detected, or many others .

FIGS. 3a to 3d now show, by way of example, the measurement signal of an observation element 1, which corresponds to the device according to Swiss patent application No. 510/92 (2/19/92, P0560), in the case of various fault locations in the scale stream. For a detailed description, please refer to the corresponding application.

FIG. 3a shows an error-free scale flow S with conveying direction F and the corresponding, continuous signal MS from the observation point over an observation time of seven cycles (T.1 to T.7). The measurement signal MS has a deflection for the edges of the printed products lying on top of the scale flow in each cycle, the time of which within the cycle corresponds to the position of this leading edge in the scale flow and the height of the product in the edge area.

FIG. 3b shows, in comparison to FIG. 3a, a shingled stream S which has an empty space in cycle T.7. Accordingly, the deflection is missing in cycle T.7 of the measurement signal. An empty space can therefore be detected by an interpretation element by scanning the measurement signal MS cyclically on an edge. If the edge is missing in one cycle, an error pulse is generated for an empty space generated. Instead of an edge scan, a height scan can also be used to detect an empty space. In the case of an empty space, the maximum height reached by the measurement signal within the cycle is below a lower tolerance limit (see description of FIG. 3c).

FIG. 3c shows a shingled stream with a double occupancy in cycle T.5. Accordingly, the deflection of the measurement signal in cycle T.5 is twice as high. For a product with a faulty thickness (missing or excess pages), the height of the deflection is correspondingly high. A scan of the deflection height can therefore be used to detect multiply occupied or incorrectly occupied locations. According to the set tolerance ranges, for example, double products in a stream of simple products, single or more than double products in a stream of double products and / or defective products in any stream can be determined.

It turns out that a tolerance range of +75% / - 50% (based on the thickness of the product) is sufficient to detect double products and empty spaces in a stream of simple products (without detection of defective products). If the measured thickness is more than 175%, there are two products, if it is less than 50% there is no product. For example, a tolerance range of ± 45% (based on the thickness of two products) is used for the detection of locations occupied by an incorrect number of products in a stream of double products. If the measured thickness is more than 145%, there are three or more products, if it is less than 55%, there is one or no product.

FIG. 3d shows a scale flow in which the product is shifted in cycle T.4 in such a way that the corresponding deflection falls in cycle T.5 and cycle T.4 must be interpreted as an empty space. If the measurement signal is also sampled in cycles on double edges, a shifted product can be detected as a cycle without deflection (T.4) with an immediately following or immediately preceding cycle with a double edge. If the phase shift between the system cycle and scale flow at the observation point is such that the edge of the product falls in the middle of the system cycle, the tolerance range of such a detection is approximately ± 50% (based on the distance between the products), i.e. a shift by more than half of the target distance is detected as a shifted product. To reduce the tolerance range, the system cycle can be divided into two areas, whereby an edge is expected in one area of the cycle and not in the other area.

Different observation elements deliver different measurement signals. With observation elements that continuously measure a quantity that correlates with the thickness of the current or the individual products, all of the errors mentioned can be detected with one flank and one height scan per system cycle if the measurement accuracy is sufficient. With observation elements that deliver a clocked measurement signal, it is sensibly only scanned for the height, that is to say that a signal of this type cannot, for example, be used to distinguish between a strongly shifted product and an empty space combined with a double product. For this reason, observation elements that deliver clocked measurement signals are advantageously used on well-clocked scale streams.

Measuring signals that are correlated with the entire thickness of the shingled stream are more complex to process because fault locations extend over several cycles, which is particularly evident at the beginning and at the end of a shingled stream and in the case of larger interruptions. If this has to be included in the interpretation of the measurement, the setpoints for cycles following an error location must be changed according to the length of the product and the location of the error.

FIG. 4 now shows an exemplary block diagram for an interpretation element 2 for interpreting the measurement signal of an observation element in the form of a device according to the Swiss application No. 510/92 (February 19, 1992, P0560), as they are also used in the application of FIG. 2 could. The stream of shingles is, for example, a stream of double products. The observation element delivers a continuous measurement signal MS. This is correlated with the height of the product edges on the scale stream. The measurement signal is processed by the interpretation unit in cycles, that is, a cycle is interpreted as faulty in a certain way and a corresponding error signal is generated or it is interpreted as good and no error signal is generated.

The measurement signal MS is fed to an edge scan 41, in which it is scanned for the number of edges occurring in cycles. If a clock has no edge, an error signal is generated for an empty space (c, FIG. 2), if it has more than one edge, an error signal for a shifted product (which, for example, is to be treated as a multiple-occupied position, b, FIG. 2) 2) generated. The measurement signal is further fed to a first, coarse height scan 42. If the maximum height reached in one cycle lies outside the tolerance range, an error signal is generated for a location occupied by an incorrect number of products (b, FIG. 2). After that the measurement signal is also fed to a second height scan 43 with a significantly narrower tolerance range. If the height is outside the tolerance range, an error signal for a defective product (a, FIG. 2) is generated. A pulse for a counter Z can be generated for a cycle that has an edge and a height that is within the narrow tolerance, so that the counter counts all good digits of the scale stream.

If a stream with individual products is treated with the same arrangement, a height below the lower tolerance limit must be interpreted as a blank (c) in the first height scan 42. If defective products and multiple products are to be discharged at the same location, the rough height scan 42 is unnecessary. If defective products need not be recognized, the second, fine height scan 43 is unnecessary.

If the shingled stream treated is a differentiated stream, in which, for example, pairs of products are conveyed, the product distance within the pair being smaller than between pairs, two or no flank alternately fall into one system cycle. The edge scan can then be set up in such a way that error signals are generated if edges occur in the empty cycle and if more or less than two edges occur in the other cycle. For differentiated currents, the system clock can also be divided into clock areas such that a pattern of clock areas with an edge and clock areas without an edge is created.

If the observation element delivers a clocked signal, the edge scanning is omitted and, depending on the size of the shift, shifted products are not detected or are detected as a combination of a multiple-occupied position and a blank space. If the measurement resolution of the observation element is not large enough or the background of the measurement is unstable, the detection of defective products (missing pages etc.) becomes difficult or impossible. If the measurement signal is correlated with the thickness of the entire stream of shingles, the interpretation of the height scan must not only be matched to the product at the top of the shingle stream, but also to all products below it.

Depending on the embodiment, the observation element can deliver an analog or a digital measurement signal. The functions of the interpretation element can be implemented in hardware or software. For both cases, the necessary functions of the conversion of the measurement signal (e.g. analog / digital converter), the edge scan (e.g. flip / flop circuit) and the height scan (e.g. comparator circuit), which may be necessary, correspond to the state of the art and need not be described in detail here .

For an analog measurement signal in the form of a measurement voltage U and a hardware interpretation unit, the limit values for the height sensing are determined, for example, by potentiometers which are connected upstream of the comparator setpoint inputs and / or by fixed resistors. The thickness of the product can be determined by the observation element during a calibration measurement and the corresponding mean setpoint can be set in the form of a reference voltage by the settings of a potentiometer. Figure 5 shows schematically the setting of this setpoint. The product thickness D is plotted on the abscissa and the comparison voltage UV is plotted on the right. Each comparison voltage is assigned, for example, two upper and two lower tolerance limits TG.1 / 2/3/4. The measurement voltage U is plotted on the ordinate.

The thickness of a product measured in a calibration measurement is D₀, the detection of which by the observation element generates a measurement voltage U₀. The comparison voltage is now set, for example, in such a way that the comparison of U and UV gives a result within the narrower tolerance limits TG.1 and TG.2. The setpoint UV₀ and the corresponding tolerance limits TG₀.1 / 2/3/4 are determined. When scanning the scale flow, the setpoint UV₀ is kept constant and the corresponding tolerance limits TGgr.3 and TG₀.4 are compared with the effective, constantly changing measured value U.

FIG. 6 shows a block diagram of an exemplary control element 3. The control element generates control pulses for the controlled elements from the error pulses generated by the interpretation element by essentially delaying them according to the distance between the observation point of the observation element and the action point of the controlled element and, if necessary, converting them in such a way that it is suitable for controlling the controlled element. The distance between the two positions is processed as the number of system cycles, which is necessary for the promotion of a product from one position to another.

If the observation element observes the same product edge (front or rear edge) on which the controlled element acts, the necessary delay corresponds to the effective distance between the observation point and the action point. If the leading edge is observed and the rear edge is knitted, the effective distance between the observation point and the point of action must be increased by the product length. If the rear edge is observed and the front edge is worked, the effective distance between the observation point and the effective point must be shortened by the length of the product.

So that the delays can be adapted as precisely as possible to the distances and the product length, it is advantageous to divide the system clock for the control unit.

The block diagram shown in FIG. 6 applies, for example, to the control element which is used for the exemplary application shown in FIG. 2, but can also be used for other applications with three or less controlled elements. The inputs for error pulses are designated in a manner corresponding to FIG. 2 with the reference symbols d, e and f, and the outputs for the control pulses with the reference symbols of the controlled elements 10, 20 and 30. The control element also has an input L for inputting the product length, which must be converted into cycles in a conversion element 61. It also has an input for the system clock T, which is advantageously converted into a faster control clock by a divider 62. The control element essentially consists of units which operate in parallel to one another and which each cause the delay of a control pulse intended for a specific controlled element. These consist of a first delay unit 63, which causes a delay by the product length and which can optionally be bypassed (switch 64), and a second delay unit 65, which is set according to the distance between the observation point and the point of action of the corresponding controlled element (input 66) . The block diagram shown is not applicable for the control of a controlled element which acts on the leading edge while the trailing edge is observed (negative delay).

For the application according to FIG. 2, the switches 64 for the inputs d and e must be bypassed and the corresponding switch for the input f first delay unit can be set, since the leading edges are observed and the controlled elements 10 and 20 act on the leading edges and only the controlled element 30 acts on the trailing edges.

In terms of hardware, the control element can be implemented, for example, with correspondingly adjustable shift registers. It can also be implemented in software.

FIG. 7 shows the operating and setting panel for a combined, hardware-based interpretation and control element. This shows which parameters can be set and which are hard-wired. The corresponding combined element can be used for the controlled elimination of multiply occupied locations from scale streams of individual products or of double products.

In the right part there are three selection buttons 71, 72 and 73. With button 71 the height scanning of the interpretation unit is activated, with button 72 the edge scanning. Edge scanning and / or height scanning can be activated. With the selection button 73, a product length-related delay can be activated / deactivated. In the middle part, the figure shows an entry point 74 for entering the product length.

The left area of the panel is used for calibration measurement and the visual display of defects. It comprises an arrangement of light-emitting diodes 75, 76, 77 and 78 and a taring button 79. The light-emitting diodes are wired to the comparators (see FIG. 8) in such a way that the green light-emitting diode 75 lights up when the measured value is within the tolerance limits TG.1 and TG .2 (Figure 5) lies. The yellow LEDs 76 and 77 light up when the measured value is between TG.2 and TG.3 or between TG.1 and TG.4. The red LED 78 lights up when the measured value lies outside the range between TG.3 and TG.4. The calibration setting is carried out in that a product or a number of products corresponding to the scale flow is detected by the observation element and the tare button 79 is set such that the green light-emitting diode 75 and the two yellow light-emitting diodes 76 and 77 light up. In operation, the position of the buoyancy control 79 is no longer changed. The diodes light up in accordance with the measurement, in particular the lighting up of the red diode 78 indicates a fault location.

FIG. 8 shows the wiring of the calibration and error detection function (height scanning) which is based on this area (75, 76, 77, 78, 79) of the panel described in connection with FIG. 7 and its function.

The controlled elements are mostly known elements that do not need to be described in more detail here. The best way to discharge defective products or multiple products is to use a release device that acts on a clamp that transports such a product. Brackets that can be individually controlled by a triggering device are known, for example, from Swiss patent 644816 (F113) by the same applicant. As already mentioned, it is more advantageous to grasp the products to be discharged at a transfer with a clamp and later to open the clamp by means of a trigger device than not to close them during the transfer. A suitable arrangement with a quick-release cylinder, which acts on the release mechanism of the clip, can be used, for example, as the release device.

A clamp buffer can be used to close gaps, as shown in FIG. A corresponding clip buffer is known from US Patent No. US-4887809 (F245) by the same applicant. Of course, other types of buffers or gap closers can also be used. However, it is advantageous to arrange the gaps at the end of the effective range of the error management system and to select such an embodiment of a gap-closing device for which the product flow need not be brought into another transport formation if possible and for which it is not possible, for example, again multiple vacancies arise.

It goes without saying that several fault management systems as described can also work together in parallel or in series. In particular, a parallel network of error management systems is conceivable for a further processing system in which several streams of shingles converge, such as for insertion or collection. All shingled streams can be processed by one fault management system, whereby fault pulses from one shingled stream can also be directed to controlled elements of the other shingled streams, for example to prevent the production of defective products.

Claims (22)

1. A fault management system for the processing of an imbricated flow of flat products, in particular of printing products, characterised in that it has an observation element (1) to produce a measurement signal (MS) correlated with the impricated flow (S), an interpretation element (2) to interpret the measurement signal and to generate fault impulses on the occurrence of gaps, sites occupied by several items, sites occupied by faulty products or sites occupied by products displaced in conveying direction, a control element (3) to generate control signals correlated with the fault signals and at least one controlled element (4.1/2/3, 10, 20, 30) arranged downstream in product flow from the observation element, to eliminate fault sites, for the conversion of fault sites into other fault sites or for the correspondingly controlled processing of fault sites and that the interpretation element, control element and controlled elements are subjected to the same system cycle.
2. A fault management system according to Claim 1, characterised in that the observation element (1) is a sensor arrangement for the timed production of a measurement signal correlated with the thickness of the products conveyed in the imbricated flow, which sensor arrangement is likewise subjected to the system cycle.
3. A fault management system according to Claim 1, characterised in that the observation element (1) is a sensor arrangement for the continuous production of a measurement signal (MS) correlated with the thickness of the products conveyed in the imbricated flow.
4. A fault management system according to Claim 3, characterised in that the measurement signal of the observation element is correlated with the thickness of the edge of the printing produced lying on top on the imbricated flow.
5. A fault management system according to one of Claims 1 to 4, characterised in that the interpretation element (2) has scanning and comparing means (42,43) for the timed scanning of the measurement signal as to its level and to compare the measurement signal level with at least one tolerance threshold.
6. A fault management system according to Claim 5, characterised in that the interpretation element (2) has input means to feed in tolerance thresholds.
7. A fault management system according to Claim 5, characterised in that the interpretation means (2) has adjustment means (79) to set nominal values with which tolerance thresholds are fixedly associated, in accordance with a calibration measurement.
8. A fault management system according to one of Claims 1 to 4, characterised in that the interpretation element (2) has means for edge scanning (41) of the measurement signal.
9. A fault management system according to one of Claims 5 to 8, characterised in that the interpretation element (2) has both means for a timed level scanning (42,43) and means for an edge scanning (41) and that it additionally has switching means (71,72) for the selective activation or deactivation of the scanning means.
10. A fault management system according to one of Claims 1 to 9, characterised in that the control element (3) has at least one delay means (65) to delay a fault signal produced by the interpretation element.
11. A fault management system according to Claim 10, characterised in that the delay means (65) is adjustable according to the distance between the observation site of the observation element and a controlled element.
12. A fault management system according to one of Claims 9 or 10, characterised in that the control unit (3) has at least one further delay means (63), which is adjustable according to the product length.
13. A fault management system according to one of Claims 10 to 12, characterised in that the delay means (63,65) are shift registers.
14. A fault management system according to one of Claims 10 to 13, characterised in that the control element (3) has a cycle divider (62).
15. A fault management system according to one of Claims 1 to 14, characterised in that the controlled element or elements (4.1/2/3. 10, 20, 30) has/have controlled means to close gaps, to remove products or to interrupt a processing.
16. A fault management system according to Claim 15, characterised in that a controlled means is a release apparatus for the controlled opening of an individual transport clip.
17. A fault management system according to Claim 16, characterised in that the release apparatus has a quick switching cylinder which acts in a controlled manner on the opening mechanism of a transport clip passing through its range.
18. A fault management system according to Claim 15, characterised in that a controlled element is the input of a clip buffer.
19. A fault management system according to one of Claims 1 to 18, characterised in that the control element also processes fault impulses from other process units.
20. A fault management system according to Claim 19, characterised in that the control element processes fault impulses of the rotary press laying out the imbricated formation.
21. A fault management system according to one of Claims 1 to 20, characterised in that its controlled elements are also controlled by other process units.
22. A fault management system according to Claim 21, characterised in that at least one of its controlled elements is, at the same time, a controlled element of other fault management systems operating in parallel in a composite arrangement.

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