EP2783354B1 - Method for monitoring transport processes for conveying banknotes in a self-service terminal - Google Patents

Description

The present invention relates to a method for monitoring transport processes for conveying notes of value according to claim 1 and a self-service terminal with a device executing the method according to the independent claim.

In an ATM, but also in other self-service terminals, such as self-payer cash register systems, the accepted or issued notes of value (banknotes, checks, vouchers, etc.) must be transported safely and reliably, e.g. from the banknote storage to the dispensing slot of the machine. In particular, it must be ensured that the notes of value are transported individually and do not overlap or overlap during transport. It must be possible to precisely record every note that is transported in order to be able to ensure, in particular, that the different note values can be counted and sorted. In order to detect the notes of value and to control the transport system, the notes of value are usually guided through at least one light barrier according to their length. Each light barrier has at least one light-sensitive sensor that reacts to optical changes in state (light-dark or dark-light). Thus, in particular, the The beginning (front edge) and / or the end (rear edge) of the individual note can be detected. A device for handling and transporting notes of value is, for example, in the DE 10 2010 004580 A1 described. The conventional optical scanning of notes of value can lead to problems if individual notes of value have viewing windows which are provided as additional security features. This is because the appearance of viewing windows when scanning the notes leads to several status changes being reported one after the other, so that it can be difficult to precisely detect the leading and / or trailing edge of the respective note.

From the WO 03/023724 A2 describes a detection system for optical media in the form of banknotes and other bank notes. The system is designed to detect or recognize viewing windows, i.e. transparent areas, in the notes of value. For this purpose, a light barrier system is installed, which has an optical transmitter and two light-sensitive sensors, which are arranged in different positions. One sensor detects the light reflected from the note as the bank of value passes through; the other sensor detects the light passing through as soon as a window appears. Thus, the occurrence of the different edges, namely the front and rear edges on the one hand and possibly window edges on the other, can be detected. However, this solution depends on the windows that appear have a sufficiently good transparency, which is not always the case. The transparency of the windows can be very low due to soiling of the bank notes or due to deliberately semi-permeable or opaque and / or colored windows. If there are windows with a low level of transparency, reflections can even result in a Window edge is erroneously detected as the front or rear edge of a note and consequently the control of the transport system works incorrectly.

From the EP0070621 a device and a corresponding method are known in which the transport of notes of value is monitored with a light barrier. Holes in the banknote are recognized by integrating the generated signals across the width of the banknote.

Further prior art is provided in U.S. 5,455,659 A , EP 0 080 158 A2 , EP 0 884 652 A2 disclosed. In addition, the article " Prepunched Paper Feed "by DR Blankenship et al, published in the IBM Technical Disclosure Bulletin, Vol. 25, May 1983, at pages 6524-6526 describes a method for a safe paper feed of prepunched copy paper.

The object of the present invention is therefore to provide a method for monitoring the transport processes of notes of value which ensures reliable control of the transport processes even for those notes of value which have windows.

The object is achieved by a method having the features of claim 1.

Accordingly, it is proposed that, in order to suppress the detection of windows and to detect the rear edge of the respective banknote, the signal generated by the sensor located in the light barrier is debounced by freezing the state of the signal generated by the sensor during a debouncing time, the debouncing time depending on the length of the note is set to a first period of time which corresponds to the expected length of the note at a given transport speed, and wherein the debouncing time is set to a second period of time that is shorter than the first period of time after the first period of time has elapsed.

As a result, a debounce time that is dynamically adapted to the length of the bill is used, which suppresses the occurrence of windows and always ensures reliable detection the rear edge, regardless of whether and what types of windows the respective note may have. For example, if a note has a length that (at the given transport speed) corresponds to 60 ms, the debouncing time is set to a first duration of 60 ms. The value note transport and its control can thus be carried out safely and reliably. Then the debounce time is set to a second shorter time period after the first time period has elapsed (for example 60 ms), which is shorter than the first time period. The second period is, for example, only 1 ms. This ensures that after the length-dependent first period of time (e.g. 60ms) has elapsed, the sensor signal is only subjected to a relatively short debounce time, since no more windows are to be expected at the end of the note and thus prompt detection or reporting of the trailing edge can be done.

The invention is based in particular on the following findings: By debouncing the sensor signal over a longer debouncing time (first period of time), the occurrence of windows can be effectively suppressed. However, the front edge of the note often cannot be debounced generously, since in many applications the front edge has to be reacted to quickly and in a time-critical manner, for example when switches have to be set within the transport system. In addition, excessive debouncing of the rear edge would also be problematic in certain applications, namely when, for example, the note passes through a stop light barrier on a roller storage system or is to be detected by the pull-off sensor on a separating and stacking module.

The above-mentioned problems can advantageously be solved by the dynamic debouncing proposed here, in which the debouncing of the rear edge when the front edge occurs is set to the expected note length.

The invention also proposes a self-service terminal which is equipped with a device operating according to the method.

Advantageous embodiments of the invention emerge from the subclaims.

The debounce time is set to a first, larger period of time as soon as the signal generated by the sensor indicates the first occurrence of the leading edge of the note. As a result, the debouncing time is started immediately when the front edge of the bill occurs or if there is a transparent window at the front edge, the end of the window occurs, the sensor signal then being debounced over the entire length of the bill.

According to the invention, the debounce time is set to a second shorter time period after the first time period has elapsed (e.g. 60 ms), which is in particular significantly shorter than the first time period, in particular less than a value that corresponds to 5 percent of the length of the note. The second time period is, for example, only 1 ms.

The self-service terminal according to the invention according to claim 3 is equipped with a device operating according to the method for monitoring the transport processes, the device having signal processing that is used to suppress the Detection of windows and, for detecting the rear edge of the note, debounces the signal generated by the sensor, the signal processing setting the debounce time as a function of the length of the note to a first time period which corresponds to the expected length of the note.

The signal processing is preferably designed as a digital debouncing unit. The signal processing can also be integrated into a computing unit of the self-service terminal. The self-service terminal can be designed as an ATM, for example.

Fig. 1

zeigt für fünf beispielhafte Situationen den Signalverlauf des Sensor-Signals jeweils ohne und mit Entprellung;

Fig. 2

zeigt die dynamische Änderung der Entprellzeit während des Durchlaufs eines transportierten Wertscheines; und

Fig. 3

zeigt den Aufbau einer Vorrichtung zur Durchführung des Verfahrens zum Überwachen von Transportvorgängen

The invention and the advantages resulting therefrom will now be described in more detail with reference to the accompanying drawings, which reproduce the following schematic representations:

Fig. 1

shows the signal curve of the sensor signal for five exemplary situations, each with and without debouncing;

Fig. 2

shows the dynamic change in the debounce time during the passage of a transported note; and

Fig. 3

shows the structure of a device for carrying out the method for monitoring transport processes

the Fig. 1 shows the signal curve of the sensor signal with and without debouncing based on five situations. The two signal curves above relate to a banknote that has no windows and a length of 60 ms through the light barrier (see also Fig. 3 ) is equivalent to. That of the photosensitive Signal S0 generated by the sensor has a first rising edge when the leading edge occurs. The time of this change of state (light-dark) is marked here with TFA. The sensor signal S0 then remains at one level until the trailing edge occurs (next change of state from dark to light at time TFE). Since in this first example the bill does not have a window, the detection of the front and / or rear edge cannot be disturbed either. Nevertheless, according to the invention, when the first edge occurs, that is to say here when the front edge occurs at time TFA, the debouncing time dT for the sensor signal S0 is set to a predeterminable value. The debounce time dT corresponds to the expected note length and is here, for example, 60 ms. For this period of time, the state of the sensor signal S0 is more or less frozen. Only after the debounce time dT has elapsed is the sensor signal processed with a very short debounce time of, for example, 1 ms. That in signal processing (see also Fig. 3 ) dynamically debounced signal S0 'follows the sensor signal S0 in the first example. If disturbances were to occur during the debounce time dT, these would be suppressed.

So that the debounce time dT for the passage of the note can be adapted to its length, the length must be known. This is usually the case with disbursement processes because the notes of value to be disbursed are specified by the system and their lengths are therefore known. In the case of payment transactions, the incoming notes of value are measured in advance by a row of light barriers in order to determine the lengths of the notes of value in particular.

The next two signal curves relate to the example of a note that has a window. That Accordingly, the sensor signal shows a multiple change in status. By setting the debounce time dT to the bill length, however, the occurrence of the window is suppressed and the reliable detection of the trailing edge at the time TFE is ensured. The debounced signal S1 'runs like a windowless note. This is also the case if the note should have several windows and the sensor signal S2 should indicate a corresponding number of changes in status. In this case, too, the debounced signal S2 'runs as in the case of a windowless note. The duration of the debouncing time dT, which is adapted to the bill length, is preferably exactly the actual bill length (eg 60ms) or slightly less, so that the occurrence of the trailing edge is not suppressed by this debouncing time and the trailing edge is displayed immediately. However, the detection of the trailing edge should also be debounced somewhat, for example with a debounce time of 1 ms. The rear edge is then reported very promptly at the time TFE. The actual detection of the trailing edge takes place beforehand at time TZ and only has the effect that a time stamp is generated that is sent to the controller with the later message (at time TFE; see also the next signal curves). This then knows exactly when the trailing edge was detected.

The next two signal curves relate to a note that has a transparent window or viewing window at its beginning. The sensor signal S3 therefore only indicates the first change of state at a later point in time TFA * and then falls back to zero at TZ. The note would appear shorter according to the signal curve S3. By the debounce time dT of z..B. 60ms, however, the real value note length is taken into account and the Detection of the trailing edge is only displayed at the time TFE. The debounced signal S3 'thus runs according to the actually given conditions; the control of the transport system can be carried out safely.

The last two waveforms in Fig. 1 refer to a note that has a viewing window at its end. The sensor signal S4 therefore runs in such a way that the leading edge is correctly displayed at the time TFA, but that the signal S4 drops to zero again at the beginning of the window (time TZ) and remains at this level. Thus, the note appears shortened at its end. By setting the debounce time dT to the real note length of 60 ms, the debounced signal S4 'remains unaffected by the occurrence of the window and only falls back to zero at the point in time TFE. Accordingly, the real length of the note is taken into account and the rear edge is displayed exactly.

the Fig. 2 illustrates the dynamic setting of the debounce time dT or its change during the passage of a note through the light barrier (see also Fig. 3 ). Starting from the first occurrence of an edge (usually the leading edge) at time TFA, the debounce time dt is set to a first value dT1 which corresponds to the expected length of the note. According to the exemplary embodiment described here, the first value dT1 = 60 ms. Otherwise, ie before a leading edge occurs and after the debouncing time dT1 = 60 ms, the debouncing time dT is set to a very small value dT2, which is 1 ms, for example. The debounce time could also be reset to zero, but it is advantageous to maintain a small amount of debouncing in order to detect the trailing edge at time TFE.

The above-described method for monitoring transport processes for notes of value can be carried out by the following using the Fig. 3 described device are carried out. The device is preferably integrated in a self-service terminal, in particular in an automated teller machine, and has signal processing that is used for dynamic debouncing of the sensor signals. The bank notes or bank notes BN are guided through a light barrier which has a light-emitting element, here a light-emitting diode or light-emitting diode assembly LED, and a light-sensitive element, here a sensor S. When light-dark changes occur (e.g. at the front edge VK) and dark-light changes (e.g. at the rear edge HK), the sensor S delivers the sensor signal described above (see Fig. 1 ). A downstream signal processing unit EP carries out the described debouncing of the sensor signal depending on the expected length of the note and thus delivers the debouncing signals already described (see also Fig. 1 ).

As before, the debounce time dT is also based on the Fig. 2 is adapted to the length of the note so that the rear edge is always reliably detected and any windows that may appear do not interfere with the detection of the rear edge. This is preferably done in the following way:
The leading edge is not debounced. Before the arrival of the bank note BN, the debouncing time dT for the rear edge, corresponding to the length of the bank note, is, for example, 60 ms set. After this first debounce time has elapsed (see also dT1 in Fig. 2 ) the debounce time is set to the low value of e.g. dT2 = 1ms. Due to the long first debounce time dT1 of 60ms, for example, all windows are suppressed because no window can be longer than the note length. After 60ms, the debouncing time is set back to 1ms in order to maintain a certain debouncing of the sensor. If the light barrier is already free, every further change of status, ie the trailing edge with this slight delay, is reported together with the time stamp, which indicates when the light barrier has become free. If the light barrier is not yet free but covered, the rear edge is reported immediately as soon as the light barrier becomes free.

The solution proposed here can, for example, be integrated in an analog sensor in the slave and activated via the master. It should then only be activated for transport light barriers. If the function is switched on, the sensor will then set a debounce time of e.g. 60ms for the trailing edge with each leading edge and immediately send itself the command to switch back to 1ms in 60ms.

It is also possible to send the debounce time via PDO (process data object on a CAN bus) so that it is used for the next bank note BN. This means that the master can configure a sensor for a registered banknote. The bank notes BN can be transported lengthways or crossways. Accordingly, the length or the width of the bank note is used to set the debounce time. Here, length can mean both, the longitudinal extent of the bank note as well as its Width expansion, depending on how the banknote is transported. If it should be known that the bank note has a certain length and is inclined by N degrees, the length derived therefrom can be sent directly to the sensor. This then uses this length or the corresponding debounce time for all subsequent bank notes, provided the length value is not overwritten. This is particularly useful when several bank notes of the same size or length are used in a row. In this case, the sensor or the signal processing would not have to be reconfigured each time, but only once when the banknote length is changed. At a transport speed of, for example, 1400 mm / sec. debounce times of around 45-80 ms must be set for common banknotes (e.g. euro bills).

The invention has the particular advantage that any windows that may be present in the banknotes can no longer be seen or interfere. Signal peaks or peaks are also filtered out. In the case of shorter banknotes, the trailing edge is only reported with a very short time delay (1 ms). If it is to be expected that many of the banknotes pass through the light barrier in a certain inclined position, the second debounce time dT2 should be set a little longer, e.g. to a value of 10ms. Due to the relatively short debounce time when the trailing edge is detected, it is displayed promptly. The control of the transport system can thus be carried out safely for virtually any type of banknote.

Claims (10)

1. Method for monitoring transportation processes for conveying bills (BN) in a self-service terminal, wherein each transported bill (BN) is routed at a predefined transportation speed, according to its length or width, through a light barrier that has a light-sensitive sensor (S), in order to detect at least one edge of the bill (BN),
   characterized in that
   in order to suppress the detection of windows (W) and in order to detect the rear edge (HK) of the bill (BN) the signal (S0) produced by the sensor (S) is debounced by freezing the state of the signal (S0) produced by the sensor (S) during a debounce time (dT), the debounce time (dT) being set, on the basis of the length or width of the bill (BN), to a first period (dT1) that corresponds to the expected length or width of the bill (BN) at the predefined transportation speed, the debounce time (dT) being set to a second period (dT2), which is shorter than the first period (dT1), after the first period (dT1) has elapsed, and the debounce time (dT) being set to the first period (dT1) as soon as the signal (S0) produced by the sensor (S) indicates the first appearance of the front edge (VK) of the bill (BN).
2. Method according to Claim 1, characterized in that the second period (dT2) is shorter than a value that corresponds to 5% of the length of the bill (BN).
3. Self-service terminal having an apparatus for monitoring transportation processes for conveying bills (BN) in the self-service terminal, wherein the apparatus routes each transported bill (BN) at a predefined transportation speed, according to its length or width, through a light barrier that has a light-sensitive sensor (S), in order to detect at least one edge of the bill (BN),
   characterized in that
   the apparatus has a signal processing section (EP) that, in order to suppress the detection of windows (W) and in order to detect the rear edge (HK) of the bill (BN), debounces the signal (S0) produced by the sensor (S) by freezing the state of the signal (S0) produced by the sensor (S) during a debounce time (dT), wherein the signal processing section (EP) is designed to set the debounce time (dT), on the basis of the length or width of the bill (BN), to a first period (dT1) that corresponds to the expected length or width of the bill (BN) at the predefined transportation speed, to set the debounce time (dT) to a second period (dT2), which is shorter than the first period (dT1), after the first period (dT1) has elapsed, and to set the debounce time (dT) to the first period as soon as the signal (S0) produced by the sensor (S) indicates the first appearance of the front edge (VK) of the bill (BN).
4. Self-service terminal according to Claim 3, characterized in that the signal processing section (EP) is conditioned to perform the method according to Claim 2.
5. Self-service terminal according to Claim 3 or 4, characterized in that the signal processing section is embodied as a digital debounce unit.
6. Self-service terminal according to one of Claims 3 to 5, characterized in that the signal processing section is integrated in a computation unit of the self-service terminal.
7. Self-service terminal according to one of Claims 3 to 6, characterized in that the self-service terminal is in the form of an automated teller machine.
8. Self-service terminal according to one of Claims 3 to 7, characterized in that the known length or width of the bill (BN) is predefined in the case of disbursement processes.
9. Self-service terminal according to one of Claims 3 to 7, characterized in that the length or width of the bill (BN) can be determined beforehand by a series of light barriers in the case of deposit processes.
10. Self-service terminal according to one of Claims 3 to 9, characterized in that the debounce time (dT) can be set by a process data object on a CAN bus.

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