JPH0214244B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper sheet processing device, particularly to a paper sheet tracking device in an automatic mail processing device.

An example of an automatic mail processing device that requires this type of tracking device is a video coding desk device, and the tracking device will be explained while explaining this device. FIG. 1 is a schematic diagram of a video coding desk device, in which information written on a paper sheet 2 conveyed in the direction of arrow 1 in the figure, such as an address or a postal code, is transferred to a scanner 3, such as a video camera. The scanning information is stored in a storage device 5 connected to the scanner 3 via a cable 4.
is stored in the storage device 5 via the cable 6.
The image is projected on the cathode ray tube 7 connected to the .
A human reads the displayed information, makes a judgment, and keys the keyboard 9. The keyed results are sent to a signal processing device 10 connected to a keyboard 9 via a cable 8. The signals processed here are further sent to the printer 12 via the cable 11. Based on the signal, the printer 12 transfers the paper sheet 2 to the printer 12.
A code is printed on the surface of the paper sheet 2 when it is conveyed to the front surface. The code is further read by a code reader 13 and classified into each stacker 14 based on the reading result.

In the case of the apparatus shown in FIG. 1, the keying corresponding to the paper sheet 2 must be completed before the paper sheet 2 passes the front of the printer 12, so that the paper sheet cannot be transferred to the scanner 3. A certain amount of delay time is required after passing through the front surface until reaching the front surface of the printer 12. That is,
A sheet transport path 15 is required between the scanner 3 and the printer 12, which causes a time lag in the sheets passing between the two.

Conventionally, as a tracking method in a conveyance device for paper sheets, etc., the conveyance section is divided into a number of partial sections of appropriate length, and a paper sheet detector using a photoelectric switch or the like is used at each division. and the same number of storage circuits corresponding to the partial sections are provided, and as paper sheets are conveyed from upstream to downstream, the storage circuits are shifted from upstream to downstream at the detection timing by the photoelectric switch. A method of tracking was used. In this case, since only one paper sheet can be stored in one storage circuit, multiple paper sheets exist in one partial section on the transport path that corresponds one-to-one with the storage circuit. must not.

This means that the length of the partial section must not be longer than the minimum conveyance interval of paper sheets. In other words, the photoelectric detectors must be installed at intervals that do not exceed at least the minimum conveyance interval for paper sheets, and in the case of a long conveyance path, a large number of detectors are required. (For convenience, the above-mentioned method will be tentatively referred to as the light bar method hereinafter.) Another conventional example is to thin out a large number of photoelectric switch groups that divide the conveyance path by an appropriate number, and to There is a method in which an appropriate clock signal generated in response to the clock signal is used instead.
(For convenience, this method will be tentatively referred to as the clock method hereafter.)
That is, when a sheet of paper crosses a certain photoelectric switch, instead of the detection signal that would normally be output from the photoelectric switch that should be installed downstream, the sheet of paper passes through the photoelectric switch located downstream. However, taking into account the time that would have taken, this method uses a timer using the clock to output a detection signal as if it were output from a photoelectric switch installed downstream, as a pseudo photoelectric switch signal. However, in this method, the timing of outputting the signal from the timer is done by predicting the time when the paper sheet would have crossed the position of the photoelectric switch, which should originally be installed downstream. It is a prerequisite that the conveyance speed is accurate. However, in reality, the conveyance speed of the conveyance path is often not always constant due to speed fluctuations of the drive source, load fluctuations of the conveyance system, slippage of the conveyance path, and the like. The fluctuation in speed results in a fluctuation in the timing of the output from the timer, that is, a fluctuation in the position of the pseudo photoelectric switch. This positional variation becomes cumulatively larger as the number of photoelectric switches thinned out increases, but it is obvious that this should not exceed one partial section on the conveyance path. Therefore, there is naturally a limit to the number of photoelectric switches that can be thinned out, and in practical terms, the limit is several partial sections.

FIG. 2 is a schematic diagram of the light bar method, which is a first example of the conventional method. As is clear from the drawing,
Each of the series of photoelectric switches PS _i (i=1, 2, 3, etc., the same applies hereinafter) is equipped with an amplifier AMP _i and a resistor.
REG _i is provided for correspondence. A series of paper sheets M _p
(p = 1, 1, 3..., which does not correspond to i) is conveyed on the conveyance path 21, and when the paper sheet M _p crosses the photoelectric switch PS _i , the photoelectric switch PS _i issues an on signal. The timing signal is generated by the amplifier AMP _i .
Output TS _i . The timing signal TS _i drives the register REG _i to shift the unique conveyance code C _p of the sheet M _p from REG _i-1 to REG _i .
In this way, each time a paper sheet M _p passes over a series of photoelectric switches PS _i from upstream to downstream, a conveyance code C _p unique to the paper sheet M _p passes over a series of registers REG _i from upstream to downstream. The paper sheets are tracked by being shifted. At that time, paper sheets with the same distance between adjacent photoelectric switches PS _i-1 and PS _i
One register if longer than the interval between M _p-1 and M _p
Since the transport code C _p corresponding to the two paper sheets is included in PS _i , it becomes impossible to distinguish between the paper sheets M _p-1 and M _pi , resulting in a situation where tracking becomes impossible. Therefore, as mentioned above, the distance at which photoelectric switches PS _i should be installed is
It must not be shorter than the minimum conveyance interval of M _p .

FIG. 3 is a schematic diagram of the clock method, which is a second example of the conventional method. As an example, FIG. 3 shows a case where three photoelectric switches PS are removed from FIG. 2. In the drawing, the timer circuit TM is driven by a clock corresponding to the transport speed, and outputs a timing signal TS _i as if the three thinned-out photoelectric switches were installed. Therefore, the operation itself is the same as that of the light bar method shown in Fig. 2, and the code C _p indicating the paper sheet is shifted to the register REG _i following the flow of the paper sheet M _p . _p is being tracked.

Therefore, an object of the present invention is to provide a paper sheet tracking device that eliminates the conventional restrictions on the spacing of photoelectric switches and enables tracking of paper sheets even when an abnormality occurs in the conveyance state. It is about providing.

According to the present invention, a detector provided at the entrance and an exit of a conveyance path of a predetermined length, a means for generating a conveyance code (number) indicating the conveyance order at the entrance and the exit, and a means for generating a conveyance code (number) indicating the conveyance order at the entrance and the exit. means for measuring the conveyance intervals at the entrance and the exit, a memory for storing the conveyance intervals at the entrance and the exit respectively at addresses corresponding to the conveyance numbers, and comparison means for comparing the conveyance intervals at the entrance and the exit outputted from the memory. When the comparison results are equal, the conveyance number generated at the exit is output as is, and when the interval becomes shorter at the exit, the conveyance number generated at the exit is returned by one and excluded for that paper sheet. A paper sheet tracking device is obtained in which a code is given, and when the interval at the exit becomes long, the conveyance number generated at the exit is incremented by one and output.

According to the present invention, even if the number of paper sheets entering the conveyance path between the two photoelectric switches increases, this can be easily handled by increasing the memory capacity, so that the hardware becomes significantly lighter than in the past.

In the present invention, a section without a photoelectric switch (2
If an abnormality occurs in the conveyance status (for example, two sheets are conveyed together on the conveyance path and become separated, or a sheet deviates from the conveyance path). 2 above)
Since the off-time values of the two registers change, this change is compared by a comparator, and abnormalities in the conveyance of paper sheets can be detected and the paper sheets can be tracked. Here, as will be described later, the change in the off time due to an abnormality in the conveyance state is about 1/2 or about twice the off time in a normal case, which is extremely large. On the other hand, the change in the off time due to conveyance speed fluctuations is at most about ±10% in practical use, so the comparator is sufficient to distinguish between abnormalities in the conveyance state and fluctuations in the conveyance speed. Even if there are some fluctuations, it can be tracked reliably.

Next, the present invention will be explained in detail with reference to the drawings. FIG. 4 is a diagram explaining the principle of the present invention,
The conveyance path 15 is only provided with two paper sheet detectors PS _{101, 102} , and the length between the two detectors is here such that, for example, 24 paper sheets can be accommodated. .

FIG. 5 is a diagram showing an embodiment of the present invention, and 2
The signals from the detectors PS _{101, 102} are each
Measurement circuit 2 after being shaped by AMP _{101 and 102}
Enter 2,24. The measuring circuits 22 and 24 each include a counter that generates a conveyance order code (conveyance number) j indicating the conveyance order each time a paper sheet is detected;
It includes a counter that measures an on time corresponding to the length of the paper sheet, and a counter that measures an off time that corresponds to the conveyance interval of the paper sheet. To measure the on/off time, for example, sample the output of the AMP in a very short cycle, check whether it is high level or low level, and compare it with the previous sample point to detect the rise and fall of the signal. This can be easily done by counting the number of sample points during high level time (on time) or low level time (off time).

In the storage circuits 23 and 25, the carrier number j
The address corresponding to is determined, and the on time and off time are stored in that address. That is, in the storage circuit 23, the entrance of the conveyance path 15 (detector PS ₁₀₁
), the on-time taj _and off-time _tbj are stored for each transport number j. Furthermore, the storage circuit 25 stores the on time t _cj and the off time t _dj for each transport number j at the exit of the transport path 15 (at the location of the detector PS ₁₀₂ ).

6a and 6b are diagrams showing the storage states in the memory circuits 23 and 25, respectively. In FIG. 6a, $1, $2, $3, ..., in FIG. 6b,
1, 〓2, 〓3,... are memory circuits 23 and 2, respectively.
5, which corresponds to transport number j. Here, j = 1, $1, $2 and 〓1, 〓2
In other words, two addresses correspond to one transport number.

Here, the conveyance path 15 is connected to a series of paper sheets M _j (M ₁ , M ₂
...) is conveyed, the output signal TS _{101 of the amplifier AMP 101 is} output every time these paper sheets M _j pass through the photoelectric switch PS 101, and the output signal TS ₁₀₁ of the amplifier AMP 101 is output as described above.
Through these steps, the on time t _aj and the off time t _bj are respectively stored in the memory circuit 23 corresponding to the conveyed objects M _j in sequence. Next, the first paper leaf
As M ₁ is transported through the transport path 15, a photoelectric switch is activated.
After passing through the PS ₁₀₂ , the output signal TS ₁₀₂ of the amplifier AMP ₁₀₂ is output in the same manner as described above, passes through the measurement circuit 24, and stores the ON time t c1 of the paper sheet M ₁ in the storage circuit 25, and then the on-time t _c1 of the paper sheet M 1 is stored in the storage circuit ₂₅ . , M ₃ ... is a photoelectric switch
Each time PS ₁₀₂ is passed, off time t _d1 , on time t _c2 ,
The off time t _d2 , . . . is memorized.

In the comparison circuit 26, each time the off time t _dj is input to the storage circuit 25, t _bl , t _d1 , t _b2 and t _d2 , t _b3
and _{t d3 .}

When the off-time t _dj at the exit becomes smaller than the off-time t _bj at the entrance, this indicates that the paper sheets that came in in duplicate were separated into two during conveyance. The transport number is the previous j-
1, and the next sheet will be corrected so that there is no error. An exclusion code will be assigned to these two documents. On the other hand, when the off time t _dj becomes larger than the off time t _bj , this indicates that the paper sheet has fallen off during conveyance.In this case, the conveyance number is set to j+1, and the next sheet is will be corrected so that there are no errors. In this way, the tracking of the conveyed items is carried out correctly.

In the video coding device implementing the present invention, the sorting code input by the operator is stored in correspondence with the conveyance code (conveyance number) determined at the entrance of the conveyance path 15, and is output at the exit of the conveyance path. The classification code is read out based on the conveyance number and printed by the printer 12.

At this time, since there is no tracking means between the entrance and exit of the conveyance path 15, the configuration can be extremely simple.

FIG. 7 is a diagram explaining the operation of the present invention in detail, and shows the relationship between on-times t _aj and t _cj and off-times t _bj and t _dj . In the figure, waveform diagrams TS ₁₀₁ and TS ₁₀₂ correspond to photoelectric switches PS ₁₀₁ and PS ₁₀₂ , respectively. When the paper sheet M _j is being conveyed between the photoelectric switches PS ₁₀₁ and PS ₁₀₂ without any abnormality, the waveform becomes as shown in TS ₁₀₂ . In this case, TS ₁₀₁ and TS ₁₀₂ are transported for the same amount of time as TS ₁₀₂ , which corresponds to the distance between photoelectric switches PS ₁₀₁ and PS ₁₀₂ .
The on-times t _aj and t _cj and the off-times t _bj and t _dj corresponding to each other are the same except that they are delayed from TS ₁₀₁ .

Next, the paper sheets transported as shown in TS ₁₀₁
This shows a case where an abnormality occurs for M _j . In Fig. 7, waveforms TS′ ₁₀₂ and TS″ ₁₀₂ are photoelectric switches PS ₁₀₁ and PS ₁₀₂ .
This indicates the output signal when an abnormality occurs in the conveyance state between the two. First, as shown in FIG. _8a , when the paper sheet M ₂₆ passes through the photoelectric switch PS ₁₀₁ , the paper sheet M ₂₆ is conveyed as one sheet or two sheets overlapped with each other, as shown in FIG. 8a. While being conveyed between the photoelectric switches PS ₁₀₁ and PS ₁₀₂ , for some reason the paper sheets that have been classified are separated into two sheets M' ₂₆ and M'' ₂₆ as shown in Fig. 8b. The photoelectric switch PS ₁₀₂ corresponds to the case where two paper sheets M' ₂₆ and M'' ₂₆ have passed. Next, TS'' ₁₀₂ corresponds to the case where the paper sheet M ₂₆ deviates from the conveyance path for some reason before passing through the photoelectric switch PS ₁₀₂ after passing through the photoelectric switch PS ₁₀₁ and does not pass through the photoelectric switch PS ₁₀₂ .

Let's compare TS ₁₀₂ when the conveyance condition is normal and TS' ₁₀₂ or TS'' ₁₀₂ when an abnormality occurs. First, paper sheets, which is one of the abnormal conditions mentioned above,
Regarding the case where M ₂₆ is separated into two pieces, TS ₁₀₂ and
This will be explained with reference to TS′ ₁₀₂ . The sum of the lengths of the on time t _c26 and the off time t _d26 when the conveyance state of the paper sheets M ₂₆ is normal is the on time t _c ′ ₂₆ of the paper sheets M′ ₂₆ , M″ ₂₆ ,
Since t _c ″ ₂₆ and the sum of its off time t _d ′ ₂₆ and t _d ″ ₂₆ are almost the same, t _{c 26} + t _{d 26} t _c ′ ₂₆ + t _d ′ ₂₆ + t _c ″ ₂₆ + t _d ″ ₂₆ ... (1) holds true.

Also, the length of two overlapping t _c26 , when separated, is t _c26 < t _c ′ ₂₆ + t _c ″ ₂₆ ...(2). From equations (1) and (2), t _d26 < t Since _d ′ ₂₆ +t _d ″ ₂₆ ...(3), the off time t _d ′ ₂₆ of paper sheet M′ ₂₆ is at least longer than the off time t _{d 26 of} paper sheet M 26.
The on-time of M″ ₂₆ becomes shorter than the value of _tc ″ ₂₆ .

Next, if the paper sheet deviates, the paper sheet
The off time t _d25 of M ₂₅ when M ₂₆ is normal is the off time t _d25 of M ₂₅ when the paper sheet M ₂₆ deviates from the conveyance path, which is another abnormal state as described above. When compared to t _d ″ ₂₅ t _d25 + t _c26 + t _d26 ……(4) holds true. Therefore, the following relationship appears: t _d ″ ₂₅ > 2 × t _{d 25} ……(5).

As explained above, using equations (3) and (5), it is possible to determine whether conveyance is normal, increased, or deviated. In other words, as can be understood from Fig. 7, when an abnormality occurs in the normal conveyance state, the change that appears in the off time t _dj ' is compared to the off time t _dj in the normal case, and the length of the paper sheet is constant. When the length is limited to the range of , if two pieces overlap at the entrance of the conveyance path and separate before the exit, it can be determined that the length is clearly short, and if they deviate from the conveyance path can be determined to be clearly long.

On the other hand, as mentioned above, the fluctuation in conveyance speed in practical use is usually very small compared to the above _- mentioned abnormal conditions, and is generally about ±10% at _most . hour on time
_This means that the values of on time t _cj and off time t _dj when passing through the photoelectric switch PS ₁₀₂ may change by 20% at worst with respect to t aj and off time t _bj .

Therefore, even if there is a change in the conveyance speed, the comparator 6 can stably determine whether or not an abnormality has occurred in the conveyance state.

In the comparator 6, the paper sheet M ₂₆ as described above is
When an abnormality is detected in which the transport number is separated into two pieces, the ratio of the transport number j is shifted by 1 and the photoelectric switch PS ₁₀₁
A photoelectric switch is placed on the paper sheet with the conveyance number when it passes through the
A number is assigned by subtracting "1" from the transport number when passing through PS ₁₀₂ . Conversely, when an abnormality is detected in which the paper sheet M ₂₆ has deviated from the conveyance path, the conveyance number of the conveyed object that has passed through the photoelectric switch PS ₁₀₂ is added to the conveyance number "1". By doing the above, paper sheets can be tracked reliably.

7a and 7b show a processing flow in an embodiment of the present invention, and the operations in FIGS. 5 and 6 will be further explained with reference to FIGS. 9a and 9b. In FIG. 7a, the state of the output signal TS ₁₀₁ of the photoelectric switch PS ₁₀₁ is checked, and if the output signal TS ₁₀₁ is at the rising edge, the conveyance number j of the conveyed object M _j that has passed is counted. Also, the off time t _bj is measured and stored at the address $x ($x is the address number 2, 4, 6, etc. of the memory circuit) of the memory circuit 23 corresponding to the carrier number j, and the measured off time t _bj is stored. clear. When the output signal TS ₁₀₁ is falling, the on time t _aj is stored in the address $x (1, 3, 5...) of the memory circuit 23 corresponding to the carrier number j counted at the rising edge, and the measured on time is stored. Clear t _aj .

When the output signal TS ₁₀₁ is on (high level), the on time t _aj is counted.

When the output signal TS ₁₀₁ is off (low level), the off time t _bj is counted.

Next, in FIG. 9b, the state of the output signal TS ₁₀₂ of the photoelectric switch PS ₁₀₂ is checked, the on time t _cj off time t _dj is counted in the same way as the output signal TS ₁₀₁ described above, and the count is stored in the memory circuit 25. do. However, in the case of a rising edge of the output signal TS ₁₀₂ , in addition to the above-mentioned processing, comparison processing is performed, and the transport number j is assigned to the transport object M _j passing through the photoelectric switch PS ₁₀₂ . Next, the comparison process will be explained in more detail using FIG. 10. FIG. 10 shows a detailed flowchart of the comparison processing part, and FIG.
The address numbers of the storage circuits 23 and 25 corresponding to the carrier number j counted in the processing in the case of the rising edge of TS ₁₀₂ in Figure b, and the off time t _bj and off time t _dj stored in compare.

If the comparison results are almost the same, the conveyed object M _j
is determined to have been transported through the transport path 15 between the photoelectric switch PS ₁₀₁ and the photoelectric switch PS ₁₀₂ without any abnormality.
Therefore, the conveyance number j is assigned to the conveyed object M _j .

However, when the comparison results are not substantially the same, it can be determined that an abnormality has occurred in the conveyed object _Mj on the conveyance path 15. When the comparison result is t _bj > t _dj , the two conveyed objects pass through the photoelectric switch PS ₁₀₁ overlapped, and are separated into two objects while being conveyed through the conveyance path 15, and then pass through the photoelectric switch PS ₁₀₂ . It can be concluded that it did.
Conversely, if the comparison result is t _bj < t _dj , the photoelectric switch
It can be determined that the conveyed object that has passed through PS ₁₀₁ has deviated from the conveyance path 15. Therefore, in order to properly track the conveyed object even if the above-mentioned abnormality occurs, first of all, if the comparison result is t _bj > t _dj , the conveyance number at the photoelectric switch PS ₁₀₂ will be incremented by one. The conveyance number j is set to -1 only once, and an exclusion code is assigned to the conveyed items that have been separated into two pieces.

Conversely, if the comparison result is t _bj < t _dj , the conveyed object has deviated, so the photoelectric switch PS ₁₀₂
The transport number will be decreased by one. Therefore, the conveyance number j is incremented by 1, and the conveyance number j is assigned to the conveyed object from the +1 incremented conveyance number j.

The off time is used to detect the conveyance state, but the on time, which is stored at the same time, is used to detect jams in the conveyance path, and if the on time is long enough, it is determined that there is a jam. Ru. Further, the memory for storing the on time and off time may be cleared at a certain predetermined synchronization. for example,
Equipped with a memory that can store 200 pieces of data.
After approximately 200 messages have been sent in succession, the conveyance can be stopped for a certain period of time, and when the conveyance has stopped, the memory, comparison circuit, etc. can be cleared.

Note that there may be cases in which two sheets overlapped at the position of the paper sheet detector PS ₁₀₁ are not completely separated at the position of the detector PS' ₁₀₂ , but in this case, the above-mentioned correction of the conveyance number is necessary. The configuration may be configured so that it is not performed. i.e. paper sheet detectors PS ₁₀₁ and PS ₁₀₂
A known multiple feed separation device as shown in Japanese Patent Publication No. 52-45103 is arranged between them, and control is made to cause the comparator circuit 26 to stop correcting the conveyance number when incomplete separation of paper sheets is detected. All you have to do is give a signal.

As explained above, according to the present invention, the conveyance state of the conveyed object on the conveyance path can be monitored without restricting the installation interval of photoelectric switches due to fluctuations in the conveyance speed of the conveyance path, and the conveyance state of the conveyed object can be tracked. It's possible. To ensure more reliable tracking,
For example, if the conveyed object is a block of a certain number of items,
Possible applications include stopping the conveyance of several blocks between each block, or using a double buffer system for the memory circuits 23 and 25. It is obvious that these will naturally occur once the basics of the present invention are understood, and there is no need to argue.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a video coding device to which the present invention can be applied, Fig. 2 is a diagram showing a conventional conveyed object tracking device, Fig. 3 is a diagram showing another conventional example, and Fig. 4 is a diagram showing a conventional conveyed object tracking device. FIG. 5 is a diagram for explaining the principle, FIG. 5 is a diagram showing an embodiment of the present invention, FIG. 6 is a diagram showing the memory contents of the memory circuit in FIG. 5, and FIG.
, a diagram showing the outputs of the photoelectric switches PS _{101 and 102} in FIG. 9A and 9B are flowcharts showing the operation of the present invention, and FIG. 10 is a flowchart showing the comparison process of the present invention. In the figure, 1...conveyance direction, 2...conveyed object,
3... Scanner, 4, 6, 8, 11... Cable, 5... Storage device, 7... Braun tube, 9...
Keyboard, 10... Signal processing device, 12... Printer, 13... Code reader, 14... Stacker, 15, 21... Conveyance path, 22, 24... Measurement circuit, 23, 25... Memory circuit, 26...Memory circuit, PS _101,102 ...Photoelectric switch, AMP _101,102 ...
...Amplifier, M...Transported object.

Claims (1)

[Claims] 1 First and second paper sheet detectors provided at the entrance and exit of a conveyance path of a predetermined length, and the paper sheet being conveyed based on the output of the first paper sheet detector. a first measuring means for measuring the distance between sheets; a first code generating means for receiving the output of the first detector and generating a code indicating a conveyance order each time a sheet is sent; a first memory that stores the measured value from the first measuring means at an address corresponding to the code from the first code generating means;
a second measuring means for measuring the interval between the conveyed paper sheets based on the output of the second paper sheet detector;
a second code generating means that receives the output of the second detector and generates a code indicating the conveyance order each time a paper sheet is sent; A second memory stored at an address corresponding to the code from the code generation means is compared with a measured value read from the same address of the first and second memories, and the difference in the interval is determined as a predetermined tolerance. and a comparison means that generates a matching output when it is within the range and a mismatch output when it is outside the range, and when the matching output occurs, the obtained code is output as is, and when the mismatch output occurs. A tracking device for paper sheets, characterized in that the value of the obtained code is increased or decreased and outputted according to the magnitude relationship between the two measured values.