JPH0466453A - Accumulated feed detection of feed paper sheet - Google Patents

Abstract

PURPOSE:To make highly precise discrimination of accumulated feed of a plural number of paper sheets considering their intrinsic light transmission by time- measuring of the intrinsic characteristics of the paper sheets in a transmitted light amount of the paper sheets. CONSTITUTION:A detection sensor consisting of luminous elements 25-28 and light reception elements 29-31 is provided in a feed system of paper sheets, and at the time when the paper sheets pass through between the luminous elements and the light reception elements, a light reception time to receive a previously decided transmitted light amount and a previously set standard time are compared with a comparator by the light reception elements. The state of accumulated feed is detected on the basis of this difference between the standard time and the light reception time.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention detects when paper sheets are conveyed in a state in which more than a prescribed number of sheets overlap when they should be conveyed, and detects an abnormality. The present invention relates to a bundle conveyance detection method for preventing the occurrence of such occurrence.

[Conventional technology]

Conventionally, examples of devices to which this bundle transport detection method is applied include financial terminals such as CDs and ATMs used in financial institutions, limited express tickets sold at railway stations, and long-distance buses from airports. Automatic ticket vending machines that sell designated tickets are known.

Regarding automatic ticket vending machines, recent ones are equipped with a ticket issuing device, a coin processing device, a banknote processing device, etc., making it possible to use banknotes in addition to coins. The amount of the ticket, which is the product selected by the user, is given to the user as change, and the ticket is issued at the same time. At this time, for the cash that is the change released to the user, for coins, a storage section is traditionally provided in the coin processing device.
A fixed amount that is the sum of the coins that were previously inserted by the staff before the sales start (this type of cash is called staff reserves) plus the coins that were inserted by users after the sales started and have undergone certain processing such as identification and counting. A so-called coin circulation system is adopted, which is a structure in which coins are always stored and the system does not run out of change coins even if the staff does not have to stop the automatic ticket vending machine in operation to replenish the change coins. Ta. On the other hand, since the unit price of the banknotes handled is low and most users use low-denomination banknotes (for example, 1,000 yen banknotes), banknote processing devices are designed exclusively for low-denomination banknotes, or are designed exclusively for low-denomination banknotes (for example, 1000 yen banknotes). Even if 10,000 yen banknotes and 5,000 yen banknotes) can be used, the low-denomination banknotes inserted by users are stored in the storage (deposit-only storage) instead of adopting the circulation system as in the case of coins. Before the release of low-denomination banknotes as change for high-value banknotes, the cashier prepared a reserve in a special storage (dedicated withdrawal storage) and used only that storage. In other words, in a banknote processing device that handles high-value banknotes and does not have a structure that uses this kind of circulation system, if a low-value banknote for change is lost in the withdrawal box, an alarm will be issued and the staff will be notified, and the staff will move the banknotes to the deposit box. It was necessary to move the low-denomination banknotes inside to a special deposit box, but even then, the frequency of use of high-denomination banknotes by users was low, so the low-denomination banknotes in reserve did not decrease much. The number of transfers was extremely small, and there were few requests for improvement, and there was no practical problem.

However, due to the recent development of passenger transportation systems using Shinkansen, express trains, and express buses between regions, and the resulting dramatic increase in the number of passengers, there is a need for automation even in the sale of tickets with relatively expensive fares and charges. The opportunity to use high-value banknotes has increased dramatically. As a result, the chances of dispensing low-denomination bills as change in response to inputting high-denomination bills will naturally increase, and in banknote processing machines that do not use the above-mentioned circulating banknotes, it is necessary for staff to replenish reserves by substituting electricity. As a result, there has been a limit to labor saving.

As with coins, there has therefore been a strong demand for such banknote processing devices to adopt a circulation system, and it has become desirable to put into practical use automatic ticket vending machines that employ a circulation system for both coins and banknotes.

By the way, in an automatic ticket vending machine, the following parts are involved in discharging banknotes.

It is a banknote storage box that can be used as a reserve and is equivalent to a safe that stores low-value banknotes of the same type inserted by the user (in the case of a circulation type device, it serves as both a deposit box and a withdrawal box). (Therefore, it is also called a handout safe), a transport mechanism that collects banknotes one by one from the banknote storage box, collects them into bundles on the way, and transports them to the banknote exit, and a transport mechanism that transports the banknotes into which the user inserts cash and any kind of banknotes. After selecting whether to purchase or not and determining whether the selection is appropriate, the amount obtained by subtracting the purchase amount from the cash input amount is used as change, and after determining the most appropriate composition from among the types of coins and banknotes, Among them, for example, a control section is provided that issues an instruction to transport banknotes from the banknote storage box to a banknote exit port via a transport mechanism. Furthermore, a detection sensor consisting of a light emitting element and a light emitting element set to face each other is installed in the banknote transport path of the transport mechanism, and the amount of transmitted light when the banknote passes between these light emitting elements is measured. is successively measured, and when the amount of transmitted light falls below a predetermined value, it is determined that bills are being conveyed in an overlapped manner, and the corresponding bills are prohibited from being carried out and collected.

[Problem to be solved by the invention]

However, in such conventional heavy conveyance detection methods, the degree of overlapping of banknotes, for example, when multiple banknotes are almost completely overlapping, when they are misaligned, and when they overlap, it is difficult to detect whether the banknotes are overlapped, for example, when the banknotes are stacked on top of each other almost completely, or when they overlap with each other. If the surfaces overlap,
The amount of transmitted light differs due to different pattern planes overlapping each other, which leads to detection errors and errors may be overlooked. In particular, in the case of a circulation-type banknote processing device, the banknotes that have been put in various states after being taken out of the wallet by the user are ejected again without the use of an attendant, so the banknotes are not stored in the banknote storage box. It is desirable that the banknote bundles be stored in a stacked state with the edges neatly aligned without any bends, etc. However, if the banknote bundles are stored in the banknote storage box partially bent, or the bending of each banknote causes unevenness in the banknote bundle. This tends to cause a situation in which the particles are formed or interfere with each other, which prevents the ejection of one sheet at a time, and an abnormality is likely to occur. In addition, the banknotes that are taken out of the banknote storage box one by one are bundled with other banknotes before the banknote exit and then delivered to the customer. This hindered operation and caused confusion within the device.

The present invention has been made in view of such problems,
The purpose of the present invention is to provide a method for detecting heavy conveyance of banknotes with higher detection accuracy, as well as a method for detecting banknotes that are bent, partially deformed, or missing, etc., which cause various problems in subsequent processing. do.

[Failure to solve the problem]

In order to achieve such an object, the present invention provides a detection sensor consisting of a light emitting element and a light emitting element in a paper sheet conveyance mechanism. Second, the light emitting time during which the light emitting element emits a predetermined amount of transmitted light is compared with a preset reference time, and a heavy conveyance state is detected based on the difference between the reference time and the light emitting time.

[Effect]

According to the monitoring method of the present invention, the unique characteristics of paper sheets related to the amount of light transmitted through the paper sheets are measured over time, so that multiple paper sheets can be monitored by taking into account the light transmittance specific to paper sheets. It is possible to identify overlapping conveyance with high accuracy.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the present invention, a banknote processing device for an automatic ticket vending machine installed at a railway station or a long-distance bus starting station will be described below with reference to the drawings.

First, the schematic structure of the banknote processing device of an automatic ticket vending machine will be explained with reference to FIG. Banknotes of the same amount inserted by the person are also stored here one after another. Reference numeral 2 denotes an exit port for paying banknotes of an amount according to the user's instructions, and 3 a collection box for collecting and storing the banknotes in case any abnormality is discovered with the banknotes being transported.

Furthermore, a conveying mechanism 5 is provided following the feeding mechanism 4 for feeding out the banknotes stored in the banknote storage box 1 one by one at a constant cycle, and the above-mentioned outlet 2 is arranged at the terminal end of the feeding mechanism 5. has been done. Note that a partition (not shown) such as a panel is provided so that the customer cannot touch the internal mechanism of the device except for the exit 2.

The transport mechanism 5 includes a first transport section and a second transport section. First, the first conveying section is a pair of lower conveying rollers 6.7.
A conveyor belt 8 wrapped around a pair of upper conveyor rollers 9,
8.11 by rotating the conveying roller 6 at a constant speed by the driving force of a drive motor 12 such as a stepping motor that rotates at a constant speed in a predetermined direction. The banknotes are conveyed to the second conveyance section side while being sandwiched between them. On the other hand, the second conveyance section includes a conveyance belt 15 wrapped around a pair of lower conveyance rollers 13 and 14, and a pair of upper conveyance rollers 16.
, 17, and the conveyance roller 13 is rotated at a constant speed by the driving force of a drive motor 19, such as a stepping motor, which rotates in a predetermined direction. The received banknotes are conveyed to the outlet 2 while being sandwiched between the conveyor belts 15 and 18. Note that the rotation speed of the drive motor 12.19 is such that the rotation speed of the drive motor 12.
In order to smoothly transfer from the first conveying section to the second conveying section,
Synchronous control is being performed.

Furthermore, a detection mechanism is provided at a predetermined location in the first conveyance unit (the location indicated by the dotted line in FIG. 1) to detect abnormalities in the banknotes, abnormalities in the conveyance state, etc., and detects any abnormality. When detected, the reject mechanism 20, which is provided at the connecting portion between the first and second conveying portions and is driven forward and backward by electromagnetic solenoids, moves out into the gap between the connecting portions.
Conveyance of banknotes to the second conveyance section is prohibited, and the bills are conveyed to the collection box 3. That is, if some abnormality occurs, immediately after the normal banknote completes transport from the first transport unit to the second transport unit, the tip of the banknote corresponding to the abnormality will be transferred to the first transport unit. At a predetermined timing within the period until reaching the terminal end of the banknote, the tip 2[1a of the reject mechanism 20 is fed out to change the conveying direction to the collection box 3 side, and the abnormal banknote is stored in the collection box 3. By retracting the tip portion 20a at the point in time, the next normal banknote is conveyed to the exit 2 side.

The mechanism shown in FIG. 1 is a single transport mechanism for one type of banknote, but in order to process multiple types of banknotes, it is constructed by combining a plurality of transport mechanisms as shown.

Next, the structure of the detection mechanism will be explained based on FIGS. 2 and 3. 2 is a view showing a part of the detection mechanism and the conveyance mechanism 5 from the side of the conveyor belt 8.11, and FIG. 3 is a view from the top of the belt 11.

First, as mentioned above, the conveyance rollers 6 and 9 are each composed of a set of rollers that rotate at the same speed, and the conveyance belts 8 and 11 are also composed of a set of belts that are wound around these rollers. has been done.

Then, each set of conveyor belts 8°8.
11. Convey while holding it at 11. The detection mechanism is arranged in a gap between the conveyor belts so as not to interfere with conveyance.

That is, the supporting frames 22 and 23 of the detection mechanism facing each other are provided along the banknote transport path 24, and the upper supporting frame 22 has four light receiving elements 25, 26, 27, 28.
are provided at predetermined intervals Ll and L2 (in this example, L1=L2=45 mm) parallel to the conveying direction of banknotes, and the lower support frame 23 has light receiving elements 25 and 26, respectively. , 27, 28 are provided with light emitting elements 29, 30, 31, 32 facing each other.

Incidentally, the light receiving elements 26 and 27 shown in FIG. 3 are arranged side by side so as to be orthogonal to the transport direction X. Further, the light emitting element 30 facing the light receiving element 26 in FIG. 3 is shown by the dotted line in FIG. 2 for convenience. Further, the light receiving element 25 and the light emitting element 290 set are used as a P detection sensor, the set of the light receiving element 26 and the light emitting element 30 are used as a first T detection sensor, and the set of the light receiving element 27 and the light emitting element 31 are used as a second T detection sensor. The set of element 28 and light emitting element 32 is called an L detection sensor.

Next, the electric circuit of the detection mechanism will be explained with reference to FIGS. 4 and 5. First, an overview will be explained with reference to FIG. 4. For each set of sensors, the light emitting drive units 33 to 36 supply power for causing the light emitting elements 29 to 32 to emit light of a predetermined intensity, respectively.
is provided.

Further, the light-emitting elements 29 to 32 have light-receiving elements 2 facing each other.
Preprocessing units 37 to 40 detect optical signals from 5 to 28 and convert them into binary level signals that can be digitally processed.
Further, waveform shaping sections 41 to 44 are provided which further shape the waveforms of the signals output from the preprocessing sections 37 to 40.

Detection signals 81 to S4 outputted from these waveform shaping units 41 to 44 are input to a control unit 45 constituted by a microcomputer system, and any abnormality during transport by the transport mechanism 5 is monitored one by one. The control unit 45 also performs processing such as synchronizing the transport timing of the entire transport mechanism and supplying control signals to the transport mechanism to deal with abnormalities.

Furthermore, a more specific circuit will be explained based on FIG. Incidentally, since each detection sensor is composed of the same or equivalent circuit, the circuit shown in FIG. 5 will be explained as a representative.

In FIG. 5, the photodiode PD is the light receiving element 25.
28, and the phototransistor Tr corresponds to each of the light emitting elements 29 to 32.

First, the light emission driving section includes a clock circuit (for example, a commercially available timer IC 555 is applied) 4 that generates a clock signal of a predetermined frequency and a predetermined duty ratio.
A photodiode PD is connected to the output terminal of 6, and is driven so that it emits light when the clock signal is at the "F7" level and turns off when the clock signal is at the "H" level. In this example,
A clock signal with a frequency of 200H2 and a duty ratio of 50% is applied.

The preprocessing section includes a comparator 47 set to a predetermined amplification factor, and a phototransistor T is connected to the inverting input contact of the comparator 47.
r output signal is input, and a dark value voltage (reference voltage) Vr set by a voltage dividing resistor is supplied to the non-inverting input contact. When the voltage of the output signal of the transistor Tr is below the threshold voltage Vr, an "H" level output is generated, and conversely, when the voltage of the output signal of the transistor Tr exceeds the threshold voltage Vr, an "L" level output is generated. . Note that a unique dark value voltage is set for each sensor.

The waveform shaping section includes a differential amplifier 48 set to a predetermined hysteresis characteristic, and removes noise components from the output signal output from the comparator 47 and generates a rectangular wave with steep rising and falling edges. The control unit 4
Transfer to 5.

In addition, R in FIG. 5 is a resistor each having a predetermined resistance value,
C is a capacitor each having a predetermined capacitance, and D is a diode for removing a negative voltage component from the output signal.

Next, the operation of the automatic cash dispensing machine having such a configuration is performed in the sixth step.
The explanation will be given according to the flowchart shown in the figure. In addition, based on the output signal S1 output from the P detection sensor, mainly,
Monitor the conveyance interval between banknotes and banknotes. 1st. Based on the output signals S2 and S3 of the second T-detection sensor, the presence or absence of heavy conveyance of banknotes is mainly monitored. Based on the output signal S4 of the L detection sensor, abnormalities in the banknote itself are mainly monitored. In addition, the first T-detection sensor detects the edge portion of the leading edge and trailing edge of the bill by comparing the output signal of the light emitting element 30 and the dark value voltage, and determines the passage period from the leading edge to the trailing edge. is defined as the period for detecting heavy conveyance of banknotes.

In addition, the second T-detection sensor is set with another threshold 1 direct voltage different from that of the first T-detection sensor, and by comparing the output signal of the light emitting element 31 with another DC voltage, the flux is determined. A signal S3 corresponding to the pattern of the amount of light transmitted through each part of the banknote during the conveyance detection period is generated.

First, the customer presents his/her ID card, inputs his/her PIN number and payment amount, and if there is no abnormality in the ID card and the ID card based on the PIN number, the drive motors 12 and 19 rotate and the transport mechanism 5 is activated. At the beginning of the operation, in this embodiment, the conveyance speed is set to 600 m5), and then the feeding mechanism 4 feeds the banknotes one by one at a fixed period (in this embodiment, a period of about 90 m5 or more). Send to 5.

Then, an abnormality monitoring process, which will be described next, is performed by interrupt processing at predetermined intervals synchronized with the feeding timing of the feeding mechanism 4.

First, in a normal state, the payout mechanism 4 takes out banknotes at a predetermined period, and the transport mechanism 5 transports them at a predetermined transport speed.
As shown in FIG. 7(a), each banknote i, i+l,
l+2. is a predetermined interval! 2. Also, each banknote is first inspected by the P inspection sensor, then the T inspection sensor, and finally the L inspection sensor.
It is optically detected by the detection sensor, so it costs ¥7 (b)
), each output signal Sl, S2 . S4 is the period TPI, TSTI, TSL corresponding to the banknote part
Period TP corresponding to "H" level banknotes and banknotes in I
2. It becomes a rectangular wave that becomes "L" level at TST2°TSL2, and furthermore, a phase shift Δ1. The output signal S3 has a waveform of a pulse train indicating the amount of light transmitted through each part of the banknote.

First, in step 100, a distance 12 between banknotes is measured by a P detection sensor consisting of a light emitting element 25 and a light receiving element 26. That is, time data T p + corresponding to the reference bill interval is set in the control unit 45, and the seventh
As shown in figure (a), a plurality of banknotes i, i+l,
When l+2 are transported, the time corresponding to the transport interval of each banknote is measured one by one, and among the measurement results,
If the value is smaller than the time data TP2, it is determined that there is an abnormality. That is, in this P detection sensor, when the optical path is not blocked by the banknote, the output signal S1 of the waveform shaping section 41
On the contrary, when the optical path is blocked, the output signal S1 becomes "H" level, so the end of each bill passes through the P detection sensor?・As a result, from the time when the output signal S1 is inverted from "H#" to "L" level, the leading edge of the next banknote passes the P detection sensor, and the output signal S1 becomes "L".
” to the “I■” level.
In Figure (b), if a time interval T', 2 shorter than the specified time interval TP2 is detected, then the banknotes 1+1 and 1+2 located on both sides of the interval T', 2 are not regular banknotes or are normal banknotes. It is determined that the device is not in a transport state.

Next, in step 110, the heavy conveyance state of the banknotes is measured by the T detection sensor consisting of the light receiving elements 26 and 27 and the light emitting elements 30 and 31. That is, as shown in FIG. 8(a), when a plurality of banknotes are conveyed in a stacked manner, or as shown in FIG. 8(b),
), as shown in figure (c), a plurality of banknotes are conveyed partially overlapping each other, and as shown in figure (c), a plurality of banknotes are conveyed overlapping and tilted with respect to the conveyance direction X. Monitor abnormal conditions such as when

9 and 10 show each sensor output 32.
An example waveform of S3 is shown. For example, when a signal as shown in waveform C1 in the figure is output from the light emitting elements 30 and 31, first, the period during which the output signal s2 is at the "H" level is set as the monitoring period, and during this period the output signal The total time during which S3 is at the "H" level is measured, and if the total time τ1 is less than the preset time τ↑ (in this example, it is set to 30m5), there is no heavy conveyance state. I judge that.

Moreover, FIG. 10 shows a case where the bill is conveyed upside down compared to FIG. 9, and the detection time τ1 of the transmitted light of the light emitting element 31 is the preset time as explained in FIG. 9. 1
If it is less than 1, it is determined that there is no overlap of banknotes. In this way, it is possible to determine whether there is heavy conveyance regardless of whether the banknote is front or back. Incidentally, the period τa corresponding to the detection period of such transmitted light is caused by the pattern of the banknote, etc., and is determined experimentally depending on the type of banknote.

On the other hand, FIGS. 11 to 13 show examples of output signals 32 and 33 when a plurality of banknotes are conveyed in an overlapping state.

In these figures, the output signal S3 becomes "H" as the number of parts through which light does not pass increases.

Since the period during which the banknotes reach the level exceeds the preset value of time T, it is determined that a plurality of banknotes are being conveyed in an overlapped manner.

Next, in step 120, the length of the banknote in the conveying direction is measured by the L detection sensor consisting of the light receiving element 28 and the light emitting element 32. That is, the output signal S4 reaches the "H" level during the period from the time when the leading edge of the banknote interrupts the optical path between the light receiving element 28 and the light emitting element 32 until the end of the banknote leaves the space between the light receiving element 28 and the light emitting element 32. Therefore, measure this time. Then, the preset time data τt corresponding to the unique length of the banknote and the time τ4 at which the output signal S4 reaches the "H" level are compared, and the time τ, for example, as shown in FIG. Time data τ.

If they are equal, it is determined that a predetermined banknote is being conveyed, and as shown in FIG.
If it is larger than 1, for example, it is determined that the banknote is being conveyed at an angle with respect to the conveyance direction, and furthermore, the same figure (C
), if the time τ4 is smaller than the time data τ1, it is determined that a part of the banknote is missing.

Next, in steps 130 to 150, if any sensor detects an abnormality, the process moves to step 160, and the electromagnetic solenoid of the reject mechanism 20 is activated to transport the corresponding banknote to the collection box 2 side, In step 170, the banknotes are collected, and in step 180, which detection sensor has detected the abnormality is displayed on a display section (not shown). And step 190
In this step, it is assumed that the payment for the number of collected banknotes has not been made, and compensation processing is performed to replenish the amount.

That is, for example, when two banknotes are collected, the feeding mechanism 4 performs an additional transport operation for the two banknotes corresponding to the collected banknotes.
instruct. Then, the process from step 100 is repeated.

On the other hand, if it is determined in steps 130 to 150 that no abnormality exists, the process moves to step 200, and the bill payment operation by the conveying mechanism 5 and the feeding mechanism 4 is continued.

Then, in step 210, it is determined whether banknotes for the amount specified by the customer have been conveyed, and paper 1'1 for the specified amount is transferred.
The process from step 100 is repeated until the conveyance of step 1) is completed, and upon completion, the conveyance operation is stopped.

As explained above, according to this embodiment, a P detection sensor, a T detection sensor, and an L detection sensor are provided, and these sensors detect an abnormality related to any one of the abnormality of the banknote itself or the abnormality caused by the conveyance state. Since only the relevant banknotes are collected when a banknote occurs, more accurate monitoring can be performed.

In particular, by measuring the amount of light that passes through banknotes over time using a T-detection sensor, we can measure the transmission pattern of multiple banknotes by taking into account the transmission pattern unique to banknotes, such as the difference in the amount of light transmitted between the transparent and non-watermarked parts of the banknote. Overlapping conveyance can be detected.

Although this example shows a case where abnormalities during transportation are monitored using the basic functions unique to each sensor, monitoring accuracy can be further improved by combining the outputs of these sensors and performing composite monitoring. I can do it.

Further, the arrangement order of the P-detection sensor, the T-detection sensor, and the L-detection sensor is not limited to this embodiment, and they may be arranged in other orders.

Further, in this embodiment, the T-detection sensor is separated into a first T-detection sensor for setting the monitoring period and a second T-detection sensor for detecting the amount of transmitted light of the transported banknote during the monitoring period. However, the circuit configuration may be such that the first T-detection sensor has both functions, and the second T-detection sensor may be omitted.

Furthermore, the second T-detection sensor of this embodiment is arranged along the P-detection sensor or the L-detection sensor, and the period during which the output signal of the P-detection sensor or the L-detection sensor is at the "H" level is defined as the heavy conveyance monitoring period. You can also use it as

Further, although this embodiment has been described with respect to an automatic ticket vending machine, it can generally be applied to a heavy conveyance detection system for paper sheets.

〔Effect of the invention〕

As explained above, according to the present invention, the unique characteristics of paper sheets regarding the amount of transmitted light of paper sheets are measured with respect to time. It is possible to identify overlapping conveyance with high accuracy. Even when this method is used in a circulating banknote processing device, it is possible to detect banknotes inserted by the user that are in poor condition, such as banknotes with partial defects or bent banknotes, which may cause these problems. Since it is possible to perform appropriate processing such as separating and discarding banknotes that are likely to be damaged, it is possible to provide a highly reliable banknote processing apparatus that can promptly stack banknotes without causing confusion.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of the configuration of an embodiment of the present invention, Figs. 2 and 3 are explanatory diagrams of the configuration of the detection mechanism, and Fig. 4 is a block diagram schematically showing the electric circuit of the detection mechanism. Figure 5 is a circuit diagram showing the electric circuit in Figure 4 in more detail, Figure 6 is a flowchart for explaining the operation, and Figure 7 is for explaining the processing operation by the P detection sensor of the embodiment. FIGS. 8 to 13 are explanatory diagrams for explaining the processing operation by the T-detection sensor, and FIG. 14 is an explanatory diagram for explaining the processing operation by the L-detection sensor. Symbols in the figure: 1; Bill storage box 2; Exit port 3; Collection box 4; Feeding mechanism 5; Conveying mechanism 6, 7. 9. 10. 13゜14.16, 17; Conveyance rollers 8.11, 15, 18; Conveyance belt], 2, 19; Drive motor 20; Reject mechanism 22.23; Support frame 25.26.27, 28; Light receiving element 29. 30, 31, 32; Light emitting elements 37-40; Pre-processing units 41-44; Waveform shaping unit 45: Control unit 46; Clock circuit 47; Comparator 48; Differential amplifier R; Resistor C; Capacitor PD; Photodiode Tr; Phototransistor D; Diode Fig. 6 Fig. 9 Fig. 10 -) - Time (Q) Fig. 7 Fig. 8 Fig. 11 Fig. 12 (b) Procedural amendment dated August S, 1990

Claims (1)

[Claims] A detection sensor consisting of a light-emitting element and a light-receiving element is provided in the sheet conveyance mechanism, and when the paper sheet passes between the light-emitting element and the light-receiving element, the light-receiving element receives a predetermined amount of transmitted light. A heavy conveyance detection method for conveyed paper sheets, characterized in that the heavy conveyance state is detected based on the difference between the reference time and the light reception time by comparing the time with a preset reference time.