JPS5843787B2 - Printing condition inspection device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a printing condition inspection device.

If a printing device is used for a long time, the printing ribbon may swell and the printed characters may become unclear.

Further, even if the print head is tilted or the printing pressure is low, clear printing cannot be expected.

This invention is a printing condition detection device for monitoring the condition of a printing ribbon and a printing head of a printing device by inspecting the density and quality of printed letters so that the letters are always printed clearly. It provides:

The printing condition inspection device according to the present invention is a device for inspecting the density and quality of printed characters, etc., and includes an imaging device that scans the printed characters, etc. and outputs an image signal thereof, and an imaging device that scans the printed characters and outputs an image signal. A plurality of level discrimination and encoding devices outputting level separated data signals according to density by performing level discrimination and encoding at a reference level; The number of data indicating the presence of printing among the output level separation data is counted for each horizontal scan, and the counted value is the first
a counting means for validating a scanning line if the number is greater than a predetermined number, and storing level separation data of each level discrimination and encoding device for the scanning line in separate locations when the scanning line is validated. the memory, checking whether or not valid scanning lines appear consecutively at least a second predetermined number;
means for clearing the data stored in the memory when the data is not consecutive for a second predetermined number or more, and determining that the data stored in the memory is level-separated data whose state should be checked when the data is consecutive for the predetermined number or more; and what should be done. The present invention is characterized by comprising means for determining the printing state by comparing the data pattern based on the level separation data determined to be equal to the desired pattern with a desired pattern.

In this invention, image signals such as printed characters are level-discriminated using a plurality of different reference levels to obtain level-separated data according to density, and data patterns based on these level-separated data are compared with a desired pattern. Because of this, check whether the printed characters and numbers are clear, dark, or faint.
It is possible to inspect whether the quality is poor or illegible, and it is possible to constantly monitor the printed state.

Also, any predetermined one among a plurality of level discrimination and encoding devices.

For example, level discrimination using the minimum visually readable density level as the reference level, and the number of data indicating the presence of printing (that is, the density is higher than the reference level) among the level separation data output from the encoding device, Each horizontal scan of the imaging device is counted and it is determined whether the data for that scan line is valid.

This eliminates scanning line data that contains only noise and does not represent printed characters.

Since only the level separation data related to the scanning line whose count value is equal to or greater than the first predetermined number and is determined to be valid is stored in the memory, the storage space in the memory is occupied by the storage of unnecessary data based on noise. The storage capacity of the memory can be reduced.

Furthermore, in this invention, the valid scanning line is
It is checked whether or not they appear consecutively for a predetermined number or more, and if they do not appear consecutively for a predetermined number or more, it is assumed that the characters to be determined are not printed and that there is some kind of dirt. Since the data in the memory is cleared by using the filter, it is possible to eliminate such erroneous judgments due to contamination, and it is also possible to save storage space in the memory.

Since the data stored in the memory is judged to be level-separated data whose status should be checked only when a predetermined number or more are consecutive, it is possible to correctly judge only the characters that should be judged. It is possible, and the memory capacity is sufficient to store only the data representing the character to be determined.

Hereinafter, a case in which an embodiment of the present invention is applied to inspecting the printing state of a passbook printed by a printing device built in an automatic teller machine, a payment machine, or other bookkeeping machine will be described in detail.

In FIG. 1, a bankbook 50 has a front cover 5 and a back cover 5.
Printed paper 53 is bound inside 2a and 52b.

The printing paper 53 is provided with columns for printing the basis weight, refund amount, deposit amount, and balance.

Furthermore, Arabic numerals 54 indicating the page number are printed in a predetermined margin.

It is preferable to inspect printed numbers, etc. for all numbers in the date and amount columns, but normally, all columns are printed using the same printing ribbon and the same print head, so one print Inspecting the columns is sufficient.

In the example below, the density and quality of numbers printed in the date field are inspected.

FIG. 2 shows a passbook transport path 60 provided in an automatic teller machine, payment machine, or other bookkeeping machine.

In this example, it is assumed that the conveyance path 60 extends in the vertical direction.

The conveyance path 60 is composed of a roller 61 and a belt 62 placed on the roller 61, and the passbook 50 is conveyed in the direction of arrow C (downward) while being held between the belts 62.

Looking into this conveyance path 60 from the import entrance toward the conveyance direction, there are charge-coupled devices (hereinafter referred to as CCDs) 63 and 64 as operating elements, and passbook position detection switches 65 and 66.
are arranged sequentially, and the print head 67 is placed at an appropriate height position.
is provided.

The CCD 63 is for reading the number 54 that indicates the page number, and is provided at a position in the width direction where the number 54 passes as the bankbook 50 is conveyed (see FIG. 3b).

The CCD 64 is for reading numbers printed in the date column, and is provided at a position across the width of the date column.

The detection switch 65 is located at a height position that detects the lowest end of the passbook 50 when the lowest part of the lowest digit of the printing paper of the passed passbook 50 faces the CCD 64 (see Figure 3a), and will be described later. In the print line positioning operation, reading by the CCD 64 is started from the moment the detection signal of this switch 65 is output.

The detection switch 66 is located at a position to detect the bottom edge of the bankbook 50 when the uppermost part of the uppermost line of the printing paper faces the CCD 64 (see Figure 3c). If the reading by the CCD 64 continues until the detection signal is output, the reading is stopped by this detection signal.

In this embodiment, the CCD 64 is a primary element having one row of 256 bits, but it is also possible to use a secondary element such as 256 bits x 4.

Furthermore, as an image sensor, a packet brigade element B
BDs and photodiodes may also be used, and these are arranged in a matrix and driven by horizontal scanning and vertical scanning circuits, so that the printing surface of the passbook 50 is horizontally and
It is also possible to use a two-dimensional image sensor that sequentially reads out data in the vertical direction.

As the passbook position detection switches 65 and 66, a photoelectric switch, a micro switch, etc. can be adopted.

Now, in the date column of the passbook, it says "52-10-10J1'-
52-10-11J, ``52-11-23,'' etc., numbers representing the year, month, and day, and a bar connecting these numbers are always printed on each line (Fig. 1, (See FIG. 6), and similar numbers are printed after positioning the print line, but in this embodiment, for convenience, only the year, month, and the bar connecting them are read by the CCD 64.

FIG. 4 shows a model when l'-52-11J is read by CCD 64.

The range indicated by the rectangular chain line E is the detection area necessary to recognize l-52-11J.

The horizontal direction of area E is divided into 256 parts, and each dividing point is C.
Corresponds to 1 bit of CD64.

If L=10 mm, a resolution of 0.04 mrrt per bit can be obtained.

This can be fully achieved by using a lens 71 (see FIG. 6).

It is scanned about 30 to 60 times in the vertical direction. The number of times of scanning may be appropriately determined depending on the conveying speed of the bankbook 50 and the scanning speed in the horizontal direction.

One scan of the print surface by the CCD 64 is performed at a period of time T3, as shown in FIG.

The scanning period T3 includes a scanning period T1 and a pause period T2. For example, scanning of the scanning line S1 is completed within the scanning period T1, and after the pause period T2 has elapsed, scanning is performed on the next scanning line S2 in the next scanning period T1. As the passbook 50 is conveyed, it is sequentially scanned along each scanning line.

In FIG. 6, the passbook insertion detector 74 consists of a charging switch etc. provided near the passbook insertion slot on the conveyance path 60, and its detection signal is sent to the central processing unit (hereinafter referred to as CP).
) 70 and a passbook transport device 78.

When the passbook insertion detection signal is input, the passbook conveyance device 78 drives the rollers 61 to convey the passbook 50 on the conveyance path 60 .

After the start of transport, the transport device 78 is controlled by the CPU 70.

The feed amount counting device 75 is composed of a rotary transducer provided on the shaft of the roller 61, and is, for example, a passbook 50.
generates a series of pulses with a frequency proportional to the transport speed.

This pulse is sent to CPU 70.

The bankbook position detector 76 includes the above-mentioned detection switches 65 and 66, and these position detection signals are sent to the CPU 70 and the drive circuit 77.

The drive circuit 77 outputs three-phase clock pulses and the scan cycle signal shown in FIG. 5 to drive the CCD 64.

Each bit of data is taken out from the CCD 64 every three-phase clock pulse of the drive circuit 77, and a time-series image signal is output to each scanning line S1...Sn... every scanning period T1. .

This time-series signal is amplified by an image amplification device 72 and then sent to a processing circuit 73 as an image signal O8.

The processing circuit 73 performs processing to be described in detail later on the image signal ①O8.

For this processing, a reference timing signal STR synchronized with three-phase clock pulses and an image input signal INT synchronized with a scanning cycle signal are sent from the drive circuit 77 to the processing circuit 73.

The memory 80 contains a data pattern area and a model area.
Play with Pattern Elijah.

The data pattern area includes a memory location used as a start flag F1, a memory location used as a counter F2 for counting the number of consecutive scans, and a memory location separated into four levels as described later. Each data CMD
Data area for storing I, CMD2°CMD3, CMD4 CMAI, CMA2, CMA3, CM
A4 is provided.

Each of these data areas CMA1 to CMA4 has a capacity of 256 bits (30 to 60) capable of storing all data of one detection area E.

In the model pattern area, a model pattern of numbers to be printed in the date field that serves as a standard for determination is set in advance.

The memory 80 includes core memory, read-only memory (ROM), and random access memory (RA).
M) etc. are used, the model pattern is stored in the core memory or ROM, and the data pattern is stored in the core memory or R
It is best to store each in AM.

The display device 79 is used to display pattern discrimination results, print density, and quality inspection results, and details will be described later.

FIG. 8 shows a specific configuration of the processing circuit 73.

The timing pulse generation circuit 90 generates three types of timing pulses TP1 . . . based on the image input signal INT from the drive circuit 77 and the reference timing signal STR. T.P.
2. Generate TP3.

As shown in FIG.
A signal synchronized with TR, timing pulse TP2
is a signal whose phase is delayed by half a cycle from the pulse TP1.

Further, the timing pulse TP3 is outputted every eight pulses TP2 in synchronization with the pulse TP1.

These timing pulses TP1 to TP3 are all applied while the input signal INT is at "H" level (scanning period T1).
) are output.

Now, the image signal ■O8 from the image intensifier 72 is transferred to the level discriminator 101, 102, 103, 10 for level demultiplexing.
Sent to 4.

Each level discriminator 101-104 has a different reference level VT1.

VT2, VT3, and VT4, the image signal vO8 is level-discriminated and encoded using these reference levels VTI to VT4, and is inverted to produce a level-separated signal CMV1.
, CMV2, CMV3, and CMV4.

In FIG. 9, an image signal VO3 is shown on the scanning line S1 in FIG.
1 and the image signal VO8n is shown on the scanning line Sn.

The level of the image signal ■O8 is high for the white part, and the level becomes lower as the density of the black part becomes higher.

Since there is no black part in the area corresponding to the scanning line S1 and the area is all white, the image signal VO31 is a uniformly high level signal.

Since the scanning line Sn crosses the printed part,
The level of the image signal VO8n varies depending on the density of the print.

Among the low-level portions of the image signal VO8n, the portion indicated by Zl rapidly decreases in level and approaches the black level, so it indicates a clearly printed portion.

On the other hand, in the portion indicated by Z2, the level of the signal VO8n changes slowly.

This part Z2 shows that the printing is unclear,
For example, this can occur when the printing ribbon becomes thin and its printing ability is reduced, or when the printed area is rubbed with a finger or the like and the outline of the print becomes unclear.

Each reference level of the level discriminators 101 to 104 ■T1 to v
T4 has a relationship of VT4>VT3>VT2>VTl, and the reference level VT4 is lower than the white level of the image signal ①O8.

The level separation signal CMV1 whose level has been discriminated based on the reference level VTI represents an image formed by a division point with the highest density, and the signal CMV2 represents an image formed by a division point whose density is higher than that corresponding to the reference level VT2.

Similarly, the other signals CMV3, CMV4 are at the reference level vT3. Each image is represented by a dividing point that is darker than the density corresponding to vT4.

The reference level VT3 is set to a level corresponding to the density of printed numbers etc. that can be visually read.
Since only images darker than the density corresponding to T3 can be visually read, the level separation signal CMV3 is used as a critical signal in that sense.

Level separation signal C from each level discriminator 101 to 104
MV1 to CM'v4 are sent to AND gate 105.

The AND gate 105 is controlled by the image input signal INT, and the gate is opened when the signal INT is at "H" level, so during this time, each level separation signal CMV
1 to CMV4 are respectively sent to the next-level edge correction circuit via an AND gate 105.

The edge correction circuit is included in shift register groups 111, 112, 113, and 114 in which serial input serial output type 256-bit shift registers are arranged in four columns, and these shift register groups 111 to 114. AND circuit 11 that takes AND logic of each output of four shift registers
It consists of 5.

In each shift register group 111 to 114, the output terminal Lf-OUT1 of the first shift register is connected to the second shift register group 111-114.
The output terminal 0UT2 of the second shift register is connected to the input terminal IN2 of the register, and the output terminal 0UT2 of the second shift register is connected to the input terminal IN2 of the third shift register.
3, the output terminal 0UT3 of the third shift register is
They are respectively connected to the input terminal IN4 of the shift register.

A timing pulse TP1 is input to the shift pulse input terminal T of each shift register in the shift register group 111 to 11.4.
Every P1, each shift register reads its input and shifts its contents one bit at a time.

During the first scanning period T1, the level separation signal CMV is applied to the scanning line S1 sent through the AND gate 105.
1 is the input terminal IN1 of the shift register group 111.
The first 256-bit data is entered into the first shift register from the first shift register and shifted sequentially every timing pulse TP1, and when exactly the scanning period T1 has elapsed, the first 256-bit data is transferred to the scanning line S1.
The shift register is filled.

In the next scanning period T1, the level separation signal CM1 enters the first shift register from the input terminal IN1 to the second scanning line S2, and also enters the scanning line S1 from the output terminal 0UT1 of the first shift register. Then, the data is outputted and sent to the AND circuit 115, and from the input terminal IN2 to the second
Enter shift register.

Then, when the second scanning period T1 has elapsed, the scanning line 81. At S2, data of 256 bits each is filled into the first and second shift registers.

Thereafter, in the same manner, the level separation signal CMVI input for each scanning period T1 is input to the first shift register, the contents of the first shift register are input to the second shift register, and the contents of the second shift register are input to the third shift register. The contents of the third shift register are respectively input to the fourth shift register, and the contents of each shift register are sent to the AND circuit 115 from each output terminal 0UTI to 0UT4.

Now, with reference to FIGS. 10 and 11, consider the portion surrounded by chain lines F1 to F4 in FIG. 4.

FIG. 10 is an enlarged view of a part of FIG. 4, and FIG. 11 shows the level separation signal CMV1 obtained by scanning the image shown in FIG. 10, expressed by the symbols "0" and "1". .

At the time when the (m+4)th scanning period T1 has elapsed, data is stored in the first to fourth registers of the shift register group 111 in scanning lines (S(m+4)) to (S(m+1)). It turns out.

Then, in the (m+5)th scanning period T1, these contents are output from each shift register and sent to the AND circuit 115.

The data of the scanning line (S(m + 1)) is 12 to j2
The bit is “1” and the scanning line (S(m + 2)
), the i3 to jO bits are "1", and the data of the scanning line (S(m+3)) is "1" in the i4 to jO bits, and the data of the scanning line (s(m+4)) is "1". The data is i3
~jo bit is “1”.

However, the output of the AND circuit 115 is A of these data.
Since it is ND logic, the (m+5)th scanning period T1
The output of the AND circuit 115 in FIG.
As shown in 1, only the data of bits i4 to jo are “
1".

Similarly, the output of the AND circuit 115 in the (m+6)th scanning period T1 is the scanning line (s(m+2)) ~
Since it is an AND logic (indicated by G2) of the data of (S(m+5)), only bits i4 to jO are "1", and furthermore, AND logic is applied in the (m+7) and (m+s)th scanning periods. The outputs of the circuit 115 are i4~jO, i5~
The jo bits each become "1" (indicated by G3 and G4).

In this way, the special data "1" that appears only in one scanning line, such as the one surrounded by the chain line H, is eliminated, and the edges of printed numbers and the like in the direction perpendicular to the scanning line are adjusted.

The edge correction circuits that process the other level separation signals CMV2 to CMV4 also perform exactly the same function, correcting any smudges, blurring, or cuts occurring at the edges of the print.

In addition, in the data of four adjacent scanning lines, unless the same bit is "1", it will not pass through the AND circuit 115, so data near the top or bottom end, such as printed numbers, will be compressed to some extent. There are no particular problems.

The modified level separated signals from each AND circuit 115 are transferred to an 8-bit shift register 1 in series input parallel output format.
Each signal is sent to 16 input terminals.

A timing pulse TP2 is sent to the shift pulse input terminal CK of these shift registers 116, and the shift register 116 reads the input signal and shifts each read data every pulse TP2. Convert to bit-by-bit parallel data.

The contents of the shift register 116 are stored in 8-bit FIFO format (First-In-F 1rst-Ou).
t) Buffer register 121゜122.123,12
Sent to 4.

These FIFO buffer registers 121 to 124 are registers that sequentially store incoming data and send it out on a first-come, first-served basis.They have a capacity to store all the data in one scanning line, and have 32 8-bit stages. It consists of

Timing pulses TP3, which are output every eight timing pulses TP2, are input to the shift pulse input terminals CK of the FIFO registers 121 to 124, and the data from the shift register 116 is output every eight timing pulses TP3. is read 8 bits at a time, and the read contents are shifted to the previous stage.

With reference to FIG. 12, FIFO registers 121 to 124
has a capacity to store exactly one scan's worth of data, so the last timing pulse TP of the scan period T1
3 is sent, it means that the FIFO registers 121 to 124 have been filled with data to their full capacity, and at this time
A signal FULL is sent from the IFO register 121 to the CPU 70 as an interrupt signal.

Then, the interrupt in the CPU 70 is accepted and the FI
Data input processing from the FO registers 121 to 124 is executed.

This process is performed by the IN command. First, a selection signal SS1 specifying the FIFO register 121 is sent to the chip select terminal C8, and the 8-bit data at the front stage of the FIFO register 121 is sent to the CP via the data bus 118.
It is transferred to an accumulator in U70, and from this accumulator to data area CMAI in memory 80.

Next, a selection signal SS2 designating the FIFO 122 is output, and similarly, the 8-bit data at the forefront of the FIFO register 122 is sent to the data area CMA2 via the data bus 118 and the CPU 70.

Similarly, selection signals 883 . SS4 is sent, and the data at the first stage of each FIFO register 123, 124 is stored in each data area CMA3, CMA4.

When the data at the first stage of the FIFO register 121 is output, the signal FULL disappears because the FIFO register 121 is no longer full.

Also, when the data in the first stage of each FIFO register 121 to 124 is sent out, the first stage becomes empty, so all stored data is shifted forward by one stage, and the last stage (
The input area (input area) becomes empty and is ready for inputting data for the next scanning line.

In this way, the data in the FIFO registers 121-124 are sequentially transferred 8 bits at a time to each data area CMA1-CMA1-124.
Transferred to CMA4.

Then, during the pause period T2, each FIFO register 12
All data of 256 bits from 1 to 124 are stored in memory 80.

Note that during the pause period T2, the FIFO registers 121 to
It is also possible to transfer only the first stage data of 124.

In this case, the pause period T2 corresponds to one data input time T.
It only needs to be a little longer than 4, so it can be a very short time.

In addition, a direct memory access channel device is provided, and when there is a signal FULL, the device is provided with data area C.
It is also possible to designate the starting addresses of MA1 to CMA4 so that the data in the FIFO registers 121 to 124 are sequentially input to the data areas CMA1 to CMA4 independently of the operation of the CPU 70.

In this case as well, the pause time T2 is one data input time T4.
If it is longer than FI, at the start of the next scanning period T1
Since the FO registers 121-124 are empty, data for the next scanning line can be stored in the FIFO registers 121-124.

In this way, the FIFO registers 121-124 separate the operation of the CPU 70 from the circuits preceding the FIFO registers 121-124 regarding data input, thereby ensuring efficient processing.

Furthermore, in FIG. 8, a counter 117 counts the number of "H" level data of the output of the AND circuit 115 connected across the output of the register group 113.

The output of this AND circuit 115 is the level separation signal C]M,
Since it is an edge-corrected signal of V3, the counter 117
The number of dividing points whose density is darker than the density corresponding to the reference level VT3 is counted.

This counter 117 is reset by the signal FULL when the next scanning period T1 is started.

Since the signal FULL is output every time the scanning of each scanning line is completed, the counter 117 counts the number of division points for each scanning.

The outputs of the counter 117 and the passbook position detection switches 65 and 66 described above are stored in FIFO registers 121 to 124.
Similarly, it is read into the CPU 70 by the IN command.

Counter 117 and switches 65 and 66 are designated by selection signals SS5, SS6 and SS7, respectively.

Next, referring to FIG. 13, by reading the numbers etc. printed on the previous print line in the date column of the passbook 50 and identifying the pattern, the next line to be printed on the passbook 50 is aligned with the print head 67. The following describes the operation of positioning the printer so that the printer is positioned, printing necessary numbers, etc. in each column using the printing pad 67 after positioning, and inspecting the density and quality of the printed numbers, etc.

First, when a predetermined page of the passbook 50 is opened and inserted into the entry slot of the bookkeeping machine C (step 1), this is detected by the passbook insertion detector 74 and the passbook transport device 78 is driven, so that the passbook 50 is inserted into the transport path 60. It is conveyed downward along the (step 2).

Then, the tension position detection switch 65 is activated by the selection signal SS6.
is specified, and the output state of this switch 65 is read (step 3).

If the lowest end of the passbook 50 is detected by the switch 65 and a detection signal is output from the switch 65, the passbook 50
Since the lowest part of the bottom row of the date field has reached the position facing the CCD 64, the feed amount counting device 75 starts counting the feed amount based on this position (
At the same time as step 4), scanning of the date column of the bankbook 50 by the CCD 64 is started (step 5).

The CCD 64 first scans the first scanning line with 256
When bit data is read, these data are stored in the data area of memory 80 based on an interrupt by signal FULL.

(Step 6).

Next, the counter 117 is designated by the selection signal SS5, the counted value of the counter 117 is read, and it is determined whether the counted value is 10 or more (step 7).

As described above, the count value of the counter 117 indicates the number of dividing points in one scanning line whose density is higher than the density corresponding to the reference level VT3.

In each scanning line, the criterion for determining whether there is some kind of printed number or the like or whether it is paper noise is set as 10. If there are 10 or more division points, it is considered to be a printed number, etc., and if it is less than 10, If so, it is considered to be noise.

At the beginning of scanning the date field, the unprinted white area is being scanned, so the count value of the counter 117 is usually 1.
If it is smaller than 0, the determination in step 7 is NO and the process moves to step 8.

In step 8, it is determined whether the start flag F1 has already been set.

The start flag F1 will be described later, but since the flag F1 is not yet set at the beginning of scanning, the process moves to step 15, and the data stored in the memory 80 in step 6 is cleared.

Then, the tension position detection switch 6 is activated by the selection signal SS7.
6 is designated and the output state of this switch 66 is read (step 16), and if no detection signal has been output from the switch 66 yet, the process returns to step 6.

As the passbook 50 is transported, step 6.7,
Steps 8, 15, and 16 are repeated, and when the CCD 64 reaches the printed area, the count value of the counter 117 becomes 10 or more, so the process moves from step 7 to step 17, and flag F1 is set.

Then, in order to count the number of consecutive scans after the flag F1 is set, the content of the counter F2 is incremented by 1.

After this, the process returns to step 6 again, and while the printed portion of the CCD 64 is being scanned, steps 6゜7.17.
Repeat step 18.

When the scanning of the printed area is completed, the CCD 64 will scan the white area again, so the determination in step 7 is NO and the process moves to step 8, where the flag F is
1 has already been sold, so the process moves from step 8 to step 9.

In step 9, it is determined whether the count value of the counter F2 is 20 or more.

Since the contents of counter F2 are incremented by 1 for scanning lines for which the count value of counter 117 is 10 or more, counter F2
The content of indicates how many such scanning lines exist consecutively.

In step 9, if there are 20 or more consecutive scanning lines whose count value of the counter 117 is 10 or more,
It is assumed that numbers or the like are printed in the scanned area, and the process moves to step 10.

If the content of the counter F2 is less than 20, it is assumed that there is some kind of dirt or the like rather than numbers being printed, and the process moves to step 15 to clear the stored data.

At this time, flag F1 and counter F2 are also cleared,
Return to step 6 and repeat the same process as above.

When it is determined in step 9 that numbers etc. are printed, the determined printing line is the printing line that appears for the first time when looking from the bottom to the top of the bankbook 50, that is, the previous printing line of the bankbook 50. Therefore, the next line to be printed is the previous line viewed from the bottom to the top of this determined print line.

In preparation for positioning the next line to be printed, in step 10, the amount of feed from the bottom line of the passbook 50 to the line where it is determined that the above numbers etc. are printed is read from the counting device 75 and stored. .

Next, in step 11, the pattern based on the read data is compared with a model pattern set in advance in the model pattern factory, and pattern discrimination is executed.

In the data areas CMAI to CMA4 of the memory 80,
Four types of level-separated data CMD1 to CMD4 have already been stored by repeating steps 6.7 and 17.18.

On the other hand, since the model pattern area of the memory 80 stores in advance a large number of standard model patterns for numbers printed in the date column, any one of the data patterns, for example, consisting of data CMD3, is stored in advance. Compare a data pattern to a number of model patterns sequentially to see if there are any matches.

To compare both patterns, for example, data constituting both patterns is taken out one bit at a time, and it is determined whether each of these pieces of data match, and the ratio of the number of matching data to the total number of data is calculated, and this ratio is set to a predetermined value. If the value is greater than or equal to H, both patterns are considered to match.

The data may be compared several bits at a time instead of comparing each bit one by one.

Note that, since there are many types of numeric combinations of year and month, the object of the present invention can be achieved even by comparing either the year or the month, or one digit of the year or month.

In this latter case, numbers 0 to 9 may be stored as model patterns.

In this way, if the data pattern consisting of data CMD3 matches any one of the many model patterns, it is OK (OK), and if the data pattern does not match any model pattern, it is OK (NG). ).

If OK in step 11, step 1
Based on the feed amount stored at 0, the bankbook 50 is positioned at a position where the next line to be printed faces the print head 67 (Step 12), and after this, predetermined printing is performed on the line to be printed on the bankbook 50. (Step 13) After clearing the data in the memory 80, the flag F1, and the counter F2 (Step 14), the process moves to the step of inspecting print density and print quality.

As shown in FIG. 1, when the passbook 50 is closed, the numbers printed on it are transferred to the facing printing paper side (indicated by A), and the numbers printed on the back side are transferred. It may appear on the printed surface (this is called bleed).
(shown as B).

If there is such transfer A1 or back transfer B, etc.,
Even if the answer in step 9 is YES and it is determined that certain numbers are printed, the data patterns such as transfer A1 and transfer B are not correct number patterns, so they cannot match any model pattern. First, in the pattern determination in step 11, it is determined that the pattern is not acceptable.

In this case, it is impossible to determine the line to be printed, so a message such as "Unavailable" is displayed on the display device 79 (step 19), and the passbook is returned (step 29).

If the page of the passbook 50 is opened incorrectly and is inserted into the bookkeeping machine with the side completely unprinted open, the passbook 50
When the lower end of 0 is detected by the switch 66, YES is determined in step 16, and the passbook 50 is returned (
Step 29).

At this time, since there is no transition to step 10 or later, pattern discrimination is of course not performed.

Inspection of the print density and print quality of the numbers in the date field printed in step 13 begins in step 20.

First, the passbook 50 is transported in the direction of the passbook insertion slot, and is temporarily stopped at a position where the topmost part of the line printed in step 13 faces the CCD 64. After that, the passbook 50 is transported in the opposite direction (
(downward) (step 20), step 13
The printed part is scanned by CCD64 (
Step 21).

Then, each time scanning is completed along one scanning line, the level-separated data is stored in the data area CMA of the memory 80.
The counter 117 is stored in each of I to CMA4 (step 22), and the content of the counter 117 is read to determine whether it is 10 or more (step 23).

For the first number of scanning lines, the count value of the counter 117 is usually smaller than 10, so the process moves to step 24, and since the flag F1 has not been set yet, the process returns to step 22.

When the scanning line reaches the printed number etc., the counter 11
When the count value of 7 becomes 10 or more, the process moves to step 25, sets the flag F1, and returns to step 22.

While scanning printed numbers etc., step 22
, 23. Repeat 25.

Then, when the CCD 64 starts scanning the white part again, it is determined NO in step 23 and the process moves to step 24. Since the answer is YES in step 24, step 2
Moving on to step 6, the print density and print quality are inspected.

At this point, the numbers printed in step 13 have already been read and the data is stored in the data areas CMAI to CM.
It is stored on A4.

As will be described later, the print density and print quality are inspected by reading data CMD1 to CMD4 stored in these data areas CMAI to CMA4 and model data stored in the model pattern area. This is executed by comparing a data pattern consisting of data CMD1 to CMD4 with a large number of model patterns.

This comparison is similar to the process in pattern discrimination (step 11).

Further, if necessary, the number of data of "1" included in the data CMD1 to CMD3 is counted.

This process can use the count value of the counter 117 in step 23.

When this inspection is completed, based on the inspection results, it is determined that the image is "clear", "dense", or "quality is poor".

A message such as “unidentifiable” is displayed on the display device 79 (
Step 27).

After that, the data in the memory 80, the flag F1, and the counter F2 are cleared, and the passbook 50 is returned (step 29).
).

Inspection of print density and print quality is basically performed by comparing a model pattern with a data pattern consisting of four types of data CMD1 to CMD4 based on level-separated signals.

When the density of the printed number "5" shown in FIG. 14 is uniform throughout (when the printing quality described later is good), the density distribution is as shown on the P-P line of the number "5". A graph like the one shown in FIG. 19 will be obtained.

In Figure 19, Pl is a clear number with a dark print density.
5'', and P2 has a slightly lighter concentration distribution than Pl.

Although P3 is visually discernible (level VT3 is the limit level for visual discernment), it is a very faint case;
P4 is a number "5" so faint that it is impossible to visually identify it.
” concentration distribution.

There are four types of data CMD for printing with distribution P1.
Since 1 to CMD4 are almost the same, these data C
The data patterns MD1 to CMD4 are the same, and when compared with the model patterns, match any of the model patterns.

In the case of distribution P2, the data patterns of data CMD2 to CMD4 are the same and match any of the model patterns, but there is almost no data with the code "1" that indicates the black level in the data CMDl, and the model - Does not match any of the patterns.

In the case of distribution P3, the data patterns of data CMD3 and CMD4 are the same and match any of the model patterns, but data CMD2 and CMDI have almost no data of "1" that would cause a black level.

Furthermore, in the case of distribution P4, data CMD3 to CMD1
There is almost no data on black level "1",
The data pattern based on these data CMD3 to CMD4 does not match any of the model patterns.

For distribution P4, the data pattern according to data CMD4 may or may not match the model pattern.

In this way, by comparing each data CMDI to CMD4 with the model pattern, the density of the printed numbers is determined.

Distributions P2 to P4 occur when the printing ribbon is thin or the printing pressure is low, and it is necessary to replace the printing ribbon, set the printing pressure, etc.

Although the density varies depending on the location and the outline is unclear, such as the number "5" shown in FIG. 15, the density distribution along the Q-Q line is as shown in FIG. 20.

Each data CMD1~ whose scanning line is the Q-Q line of this distribution
In CMD4, when comparing the number of data with a black level of 1", CMD4>CMD3>CMD2>
It becomes CMDI.

Further, if the number of such a concentration distribution can be visually identified, it is determined that the number corresponds to at least one of the data patterns consisting of data CMD1 to CMD4, for example, data C
The data pattern consisting of MD2 matches the model pattern, but if the outline becomes extremely unclear and visual identification becomes difficult, none of the data patterns match the model pattern.

The density distribution shown in FIG. 15 is caused by defects in the printing ribbon, deformation of the printing surface of the print head, over-application of ink, and the like.

16 and 17 both show data CMDI
, CMD2 does not match the model pattern, but the data pattern based on data CMD3 matches the model pattern.

Figure 16 shows the case where the print head is tilted, and Figure 17 shows the case where the print head is tilted.
The figure shows a case where the printing ribbons partially overlap and the printing is darker in only those areas.

Data C among the data obtained by reading these characters
Data “1” exists in MD1 and/or CMD2.

FIG. 18 shows a case where the print head is even more tilted, and even the data pattern based on data CMD4 does not match the model pattern, but data CMDI, C
Data “1” exists in MD2, CMD3, etc.

In this way, four types of level-separated data CMDI
~ Compare the data pattern by CMD4 and the model pattern, and if necessary, use the data CMD1~C
By counting whether or not there is a predetermined number or more of "1" data in MD3, ■) It is clear (FIGS. 14 and 19 PI) 2) The quality is good and it can be identified. 3) Identifiable but poor quality (Figs. 15 to 17) 4) Print density and indistinguishable (Fig. 19 P4, Fig. 18) A print quality inspection is performed.

For these inspections, level separation data CMD1
In addition to comparing the data pattern by CMD4 and the model pattern, each data CMD1 to CMD4 may be compared with each other.

Roughly, if four types of model patterns are set in advance corresponding to each level data CMD1 to CMD4, more precise judgment will be possible.

In the flow chart of FIG. 13, there are steps 9 and 18 in data reading for pattern determination (step 11), and steps corresponding to steps 9 and 18 in data reading for print density and quality inspection. However, this is because the printed line is roughly known in the latter data reading, and step 2
This is because scanning is performed after the vertical position is determined at 0.

It goes without saying that it is preferable to provide steps corresponding to steps 9 and 18 when the printed line is not known in advance when inspecting the printing state of items other than bankbooks.

This allows level separation data to be stored for each print line.

Furthermore, by providing step 15, if the determination is NO in step 9, the data stored in the memory 80 can be cleared in step 15, so the capacity of the data area of the memory 80 is equal to one print line. It has the advantage of being able to save memory capacity since it only needs to be able to store data.

In the above example, only the date column is read by the CCD 64 and the printing condition is inspected, but if necessary, more CCDs can be arranged to inspect the printing condition of the refund amount, deposit amount, and balance column. You can also do that.

In addition, in step 20, the passbook 50 is once returned to the side of the insertion slot and positioned, and then the passbook 50 is conveyed downward again. However, a CCD for inspection separate from the CCD 64 is provided, and after printing, the passbook 50 is moved upward. It is also possible to read printed numbers and the like while conveying the paper further downward without returning it.

Incidentally, if the image signal from the CCD 63 is processed in the same manner as described above and the pattern is discriminated, it is also possible to recognize the number of pages marked with Arabic numerals 54.

In this way, if the page number is prefixed with Arabic numerals 54, it is possible to eliminate the strange feeling that the user would feel if the page number is prefixed with a bar code.

In addition, by notifying the staff of the inspection results using appropriate display means, audio notification means, etc., they can replace the printing ribbon and set the print head each time, ensuring clear printing at all times. can.

Needless to say, the present invention can be applied not only to the inspection of the printing condition of bankbooks, but also to the inspection of the printing condition of letters, numbers, and other characters printed on any paper.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the passbook, Fig. 2 is a side view showing the passbook transport path, Fig. 3 is a front view showing the passbook transport path, and Fig. 4 is an explanation showing the model when printing is read by CCD. Figure, 5th
6 is a block diagram showing an embodiment of the present invention, FIG. 7 is a diagram showing the contents of the memory, and FIG. 8 is a block diagram showing the specific configuration of the processing circuit. Fig. 9 is a time chart showing the operation of the processing circuit, Fig. 10 is an enlarged view of a portion of Fig. 4, and Fig. 11 is a time chart showing the operation of the processing circuit.
An explanatory diagram showing the model in Figure 0 with symbols, Figure 12 is CP
FIG. 13 is a flow chart showing the processing by the CPU; FIGS. 14 to 18 are diagrams showing various printed numbers; FIG. 19 is a flow chart showing the processing by the CPU; 20 is a graph showing the concentration distribution along the line PP in FIG. 15, and FIG. 20 is a graph showing the concentration distribution along the line Q-Q in FIG. 50... Passbook, 53... Printing paper, 6
0...Passbook conveyance path, 63.64...C
CD (imaging device), 67...Print head, 70
...Central processing unit CPU, 80...
・Memory, 101 to 104...Level discriminator,
111-114... Edge correction shift register group, 115... Same AND circuit.

Claims (1)

[Scope of Claims] 1. A device for inspecting the density and quality of printed characters, etc., comprising: an imaging device that scans the printed characters and outputs image signals; A plurality of level discrimination and encoding devices output level separated data signals according to density by level discrimination and encoding. counting means for counting the number of data indicating the presence of printing among the level separation data to be printed for each horizontal scan, and validating the scanning line when the counted value is greater than or equal to a first predetermined number; In this case, each level discrimination regarding the scanning line, a memory for storing the level separation data of the encoding device in separate locations, and whether or not a second predetermined number or more of valid scanning lines appear consecutively. If the data is not continuous for a second predetermined number or more, the data stored in the memory is cleared, and if the data is continuous for a predetermined number or more, the data stored in the memory is determined to be level-separated data whose state should be checked. A printing condition inspection device comprising: means for determining a printing condition by comparing a data pattern based on level separation data determined to be subject to condition inspection with a required pattern. 2. The printing condition inspection device according to claim 1, wherein the required pattern is a preset model pattern. 3. The print condition inspection according to claim 1, wherein the required patterns include data patterns based on level-separated data in addition to model patterns, and a plurality of data patterns are compared with each other. Device.