JPH0444312B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a printer loaded with paper on which identification marks indicating the type of paper, printed content, etc. are recorded, and in which the identification marks are read photoelectrically. The present invention relates to a method for reading identification marks.

[Conventional technology]

When printing on slip paper, etc., an identification (hereinafter referred to as ID) mark in the form of a bar code is recorded on a predetermined part of the paper depending on the paper type, printing content, etc., and an optical reading device records the paper content. When making identification possible or performing additional printing on paper with an ID code printed on it, it has been proposed to set the printing content according to the reading of the ID code and perform additional printing accordingly.

In other words, an ID consisting of multiple marks each having a specific width at a predetermined pitch in the line direction of the paper.
Marks are recorded, and the printer reads them photoelectrically in a fixed direction from a reference position before starting printing, identifies the paper according to the arrangement of each mark, and prints accordingly. ing.

[Problem that the invention seeks to solve]

However, if the paper is in the form of a single sheet, even if the paper is inserted along the guide, the insertion situation will be tilted, and the relative relationship between the printer's reading mechanism and the ID mark on the paper will be irregular. If reading is performed from a predetermined reference position, the reading situation will be inaccurate, leading to problems such as making it impossible to identify the paper or causing an error in identification.

[Means for solving problems]

In order to solve the above-mentioned problem, the present invention is constructed by the following means.

That is, in the above-mentioned printer, each mark is photoelectrically read in a certain direction, the first mark is detected, the width of this mark is determined, and the value of this width is divided by 1/
The center position is calculated by multiplying by 2, the reference position is obtained by subtracting 1/2 of the specific width from this center position, and the identification mark is read using this reference position as a reference.

[Effect]

Therefore, the reading start sides of the first mark actually detected are determined as reference positions, and reading is performed based on these positions, making it possible to reliably read and identify ID marks.

〔Example〕

Hereinafter, details of the present invention will be explained with reference to figures showing examples.

FIG. 2 is a side view showing the main parts of the horizontal printer, in which the paper inserted from the supply port 1 is placed facing each other on guide plates 2a and 2b arranged vertically opposite each other. It is detected by the paper feed sensor 3 such as a light emitting diode and a light receiving transistor, and as the transport motor 4 rotates according to the detection output, the gears 5, 6, the pulley 7 and the belt 8 are rotated.
The rollers 9 and 10 rotate in the direction of the arrow, and the paper is held between the holding rollers 11 and 12 that are in contact with the rollers 9 and 10, and is transported to the right in the figure.

However, between the rollers 9 and 10, a platen 13 is provided on the lower side, and a wire dot printing type printing head 14 is provided on the upper side facing the platen.
is provided, and a paper feed sensor 3 is installed on the supply port 1 side of this.
A paper edge sensor 15 similar to the above is provided, and when the leading edge of the paper is detected by this, the transport distance is determined based on this position until the printing start position of the paper coincides directly below the print head 14. Therefore, when the paper is transferred by this distance, the motor 4 stops and enters a printing standby state.

The print head 14 is operated by a mechanism not shown in the figure.
It is supported so that it can move in both left and right directions when viewed from the supply port 1 side, and can move forward and backward in a direction perpendicular to the paper surface, and the gap between the paper surface and the leading edge 14a is automatically determined according to the paper thickness. As the process starts, printing is performed while moving both left and right, and 1
When printing for a line is completed, the motor 4 rotates to perform a line feed, and then the printing head 14 prints while moving in the reaction direction, and the above operations are repeated, and the printing progresses. Accordingly, the paper is gradually transferred to the discharge port 16 on the right side in the figure.

Further, when the trailing edge of the paper passes the paper edge sensor 15, trailing green is detected based on a change in the output of the paper edge sensor 15, and the final printing position of the paper is determined based on this position.

FIG. 3 is a cutaway perspective view of the reading section showing how the printing head 14 is supported, and shows side plates 21a and 21 on both sides.
An ink ribbon cartridge 22 is installed between b, and a movable guide shaft 23 is provided on the back side of the ink ribbon cartridge 22, and the movable guide shaft 23 is movable in the vertical direction. Print head 1 to horizontal protrusion 24a
4 is fixed, and the upper opening 2 of the support base 24
4b, while it is movable in the vertical direction,
A sleeve 25 that is engaged with the support base 24 is provided in the horizontal direction, and a fixed guide shaft 26 that passes through the sleeve 25 in a sliding manner prevents the support base 24 from rotating around the movable guide shaft 23. If the movable guide shaft 23 is moved up and down by a mechanism using an eccentric cam (not shown in the figure), the printing head 1 can be moved up and down.
4 can freely move forward and backward relative to the paper surface.

Further, a printing head 14 is provided on the outside of the side plate 21a.
The motor 27 that moves the motor 27 is fixed, and as the motor 27 rotates, a part of the synchro belt 30 stretched between the pulleys 28 and 29 is considered to be the support stand 24, so the support stand 24 moves in the left and right direction. The printing head 14 is also moved accordingly.

In addition, as the motor 27 rotates, the pulley 3
An ink ribbon 34, which is stretched over the lower surface of the tip of the print head 14 through the cartridge 22 and the belt 33, is simultaneously driven and circulated in response to printing.

Therefore, the print head 14 reciprocates from the left to the right and from the right to the left in response to the forward and reverse rotation of the motor 27, and by driving the print head 14 each time it moves in both directions, it is possible to print from both directions. is printed as each line.

FIG. 4 is a perspective view showing how the ID sensor for reading the ID mark is mounted, and is attached to the horizontal protrusion 24a of the support base 24 via the mounting plate 36.
ID sensor 37 is fixed facing downward,
The ID sensor 37 is connected to the tip 14a of the print head 14.
The ID mark is optically read while moving as a unit with the print head 14, by projecting light and receiving reflected light, targeting the same area of the paper in the left and right direction.

When reading the ID mark to confirm it after printing the ID mark by yourself, for example, print the ID mark while moving the print head 14 to the right, and then print the ID mark while moving to the left. An ID sensor 37 is configured to read the ID mark.

FIG. 5 is a block diagram of the circuit configuration that performs the above control, and is implemented by a microprocessor (hereinafter referred to as
The main control unit (hereinafter referred to as
MCT) 41, and a similar but slightly smaller sub-control unit (hereinafter referred to as SCT) 42.
MCT41 includes amplification shaping circuit (hereinafter referred to as AWF) 4
The detection output of an ID sensor (hereinafter referred to as IDS) 37 is provided via the ID sensor 3, and data is exchanged with a host device such as a computer (hereinafter referred to as UCE) not shown in the figure.

In addition, the SCT 42 is given commands from the MCT 41, while the drive circuit (hereinafter referred to as DRV) 4
4, a moving motor (hereinafter referred to as SPM) 27 using a step motor is driven, and the DRV 4
A print head (hereinafter referred to as PHD) 14 is also driven via the print head 5.

Note that each CPU, such as the MCT 41 and the SCT 42, executes instructions in the memory and performs predetermined control operations while accessing necessary data from the memory.

FIG. 6 is a diagram showing the recording status and reading status of the ID mark. In A, a predetermined pitch is placed on the front edge 52 of the paper 51 in the vicinity of the leading edge 52 and in the horizontal direction in the figure. A plurality of rectangular marks 51 ₁ , 5 each having a specific width W by P
3 ₂ , 54 ₁ to 54n and 55 ₁ , 55 ₂ are recorded as black, for example, and in this example, marks 53 ₁ and 53 ₂ are start marks and marks 54 ₁
~54n is used as a code mark, marks ₅₅₁ and ₅₅₂ are used as stop marks, and between the start mark ₅₃₂ and the code mark ₅₄₁ , and between the code mark 54n and the stop mark ₅₅₁ ,
While each two marks are spaces, the code marks 54 ₁ to 54 n represent the identification code of the paper 51 using a binary code, for example, with the code mark 54 ₁ as the least significant bit and the mark 54 n as the most significant bit. Therefore, the mark to be used as a space is determined according to the content.

In addition, in B, PHD for paper 51
14 and IDS37, and while the SPM27 is driven 30 steps each from the movement limit positions _PHL and _PHR at both ends, it is an acceleration or deceleration section in which the speed S changes. The area between the boundary position P _CL and R _CR is a constant speed area in which constant speed printing or reading is performed, and in this area, approximately 1200 steps of driving are performed on the SPM 27.

Note that the ID marks 53 ₁ to 55 ₂ are printed on the paper 51 in advance or are printed via the MCT 41.
In response to the ID mark printing command from UCE, SCT42
is to be printed by driving the SPM 27 and PHD 14. In this case, ID marks 53 ₁ to 55 ₁ are printed by moving in the direction of arrow P, and ID marks 55 ₂ are printed by moving in the direction of arrow R.
~53 ₁ is successively read from the direction opposite to that of printing, this status is stored in the memory in the MCT 42, and after these operations are completed, the contents of the memory are read from the direction opposite to the direction in which it was stored, and the ID mark 53 ₁ ~ 55 ₂ is read from a certain direction along the direction of arrow P, and the printing status is checked.

FIG. 7 is a diagram showing the detection status of ID marks, for example, start marks 53 ₁ , 53 ₂ shown in A.
When detected by the IDS37, an electrical signal B is obtained, which is amplified in the AWF43 and waveform shaped using the reference level _Ls , resulting in a pulsed waveform C, whose high level is the white of the detection output B. The logic value "0" indicates that the output B is low, and the logic value "1" indicates that the output B is black when the low level is low.

However, the reading in the constant speed section of FIG. 6 is done in accordance with the driving of the SPM 27 in synchronization with the clock pulse, and the pulse-like waveform of FIG.
In the MCT 41, the start marks 53 1 and 53 2 are processed by sampling synchronized with the clock pulse, so the start marks 53 ₁ and 53 ₂ are decomposed into dots along a certain direction P. In this example, the start marks 53 ₁ and 53 ₂
are processed as if they each consist of 8 dots.

Furthermore, based on the waveform distortion shown in FIG. 7B, the width W of the start marks 53 ₁ and 53 ₂ is reduced to the pulse width x shown in FIG. Each mark 54 ₁ to 5
The same applies to 4n55 ₁ and 55 ₂ .

On the other hand, in Fig. 6, start mark 53 ₁
If the ID marks 53 ₁ to 55 ₂ are read in a certain direction P using the side 53a as a reference position P _R , these identifications can be made accurately.
When the paper 51 on which the marks 53 ₁ to 55 ₂ are printed or separately printed is inserted, the border position of the ID marks 53 ₁ to 55 ₂ is determined depending on the insertion status.
There is a deviation in the relative relationship between P _CL and P _CR , and the position of a certain number of steps from the environmental position P _CL is changed to the reference position P _R
If the ID marks 53 _{1 to 55 2 are read as follows, the ID marks 53 1} to _{55 2} will be inaccurately distinguished from the mark space, so the reference position _PR must be accurately determined according to the actual reading situation.

That is, let us assume a case where the marks after B following the start mark A as shown in FIG. 10a are to be read. FIG. 10b shows an analog signal when this mark is read, and FIG. 10c shows a signal obtained by converting the analog signal into a binary value. The CPU takes in the signal shown in FIG. 10c, and determines that the signal has an L level signal of 5 or more dots as a black level.

In this case, it is not preferable for the CPU to examine the signal c at all locations, that is, to continuously check where the black level is from time t1 to time t2, as this increases CPU processing time. As shown in FIG. 10a, the black levels are arranged only at intervals of P, so it is sufficient to examine only the timing portion corresponding to the interval, and the CPU can perform other processing at other times.

FIG. 10d is an example in which it is checked whether or not there is a black level at intervals of P from the time point when the binary signal ``ro'' corresponding to the start mark I is generated. In this example, the determination of the signal "I" starts from the part of the symbol a2, but this means checking from the middle of the binarized signal as shown in c.

The binarized signal is not generated over the entire width of the mark, but is narrower than the eight dot width of the mark. Judgment is made to the left in the diagram, so if you judge whether the black level is in the middle of the binarized signal, the black level will still be the same even if you check until the end of the signal (the right end of the binarized signal). may end up being less than 5 dots. In this figure, a2, a
4, a5 is the location, but in such a case, there is an inconvenience that it is determined that the black level is not at that location.

Therefore, in the present application, the determination is started from the time when the binary signal is generated or slightly before that time. In this way, if the width of the binarized signal is 5 dots or more, it will always be determined as a black level. 1st
Figure 0e represents this state. That is, the point before the start mark is set as the start point b1, and the search is performed at intervals of P from there. In this way, the judgment starts from the white level part, and the CPU
Although the time available for other processing is reduced, false judgments will not occur. FIG. 8 is a diagram illustrating a method for determining this starting point.

FIG. 8 is an enlarged view of the situation in which the reference position P _R is determined, and shows the relationship between the start mark ₅₃₁ stored in the memory in the direction of the arrow R in FIG. 6 and the memory address number ADR, and the boundary position If the address number ADR corresponding to P _CL is the check start address A ₃ , then the address number ADR
When the contents of the memory are read by sequentially advancing in the direction of arrow P, "1" is first read at addresses A ₁ to _{A 6} .
dots are read, and the center position P _c is obtained by multiplying the width A ₁ to A ₆ =6 dots by 1/2.

In addition, the original start mark 53 indicated by the broken line
₁ has a width of 8 dots, 1/2 of this = 4 dots, and a tolerance of 2 dots, taking into account the printing deviation of ID marks 53 ₁ to 55 ₂ and waveform distortion shown in Fig. 7, is the center position P _c If subtracted from, the reference position including tolerance
An address A _R corresponding to P _R is obtained, and the contents of the memory are successively read from this address A _R as a starting point.
ID marks 53 ₁ to 5 are determined by determining marks and spaces according to logical values of “1” and “0”.
5 Able to accurately identify ₂ .

FIG. 9 is a flowchart of the reference position judgment situation by the CPU of the SCT 42, and "SPM drive" is performed by pulse driving of the SPM 27 via the DRV 44.
101, for example, the limit position shown in FIG.
“30 step drive?” 102 from P _HR is Y
If (YES), “Read ID mark” 111 will be sent to IDS.
37, and the detection output of this is AWF43.
Then, each address is sequentially stored in the memory by the "Detection data/memory storage" 112 via the MCT 41, and the "1200 step drive?" 113 is set to N (NO).
During this time, steps 111 and subsequent steps are repeated.

When the step 113 becomes Y and the boundary position _PCL is reached, the CPU 21 further judges the ``30 step drive?'' 121 in the same way as the step 102, and if this becomes Y, stops the driving of the SPM 27 with the ``SPM stop'' 122. After that, a "reference position check" 131 is performed.

FIG. 1 is a flowchart showing the details of the "reference position check", in which the address counter "ADC←P _CL " 201, which specifies the address of the memory storing the detected data in step 112, corresponds to the boundary position P _CL . Set the address to be used, perform "memory read" 202, and check if this data is "black?" 2
11, if N, “ADC=ADC+1”
After registering the address counter ADC in step 212, steps 202 and subsequent steps are repeated.If step 211 is Y, the black dots configured in the CPU are counted in accordance with the black detection data. After clearing this with the counter “BCT←0” 213, “BCT=BCT+1” 214
It is checked by "BCT≧5?" 215 whether the count value is 5 or more and there are 5 or more consecutive black dots.

If step 215 is N, the memory read address is recommended by "ADC=ADC+1" 221 as in step 212, "memory read" 222 is performed as in step 202, and the data is "black?"
Step 223 is determined in the same manner as step 211, and when the result is Y, steps 214 and subsequent steps are repeated, whereas when step 223 is N, steps 202 and subsequent steps are repeated via step 212.

Therefore, as shown in FIG. 8, the memory address ADR is sequentially advanced from the boundary position _PCL in the direction of the arrow P, and the contents of each address are read to determine whether it is black or white, and the black dot is Until five consecutive dots are first detected and step 215 returns Y, even if black dots are detected discontinuously, they are ignored as noise or paper smudges.

If the start mark ₅₃₁ is first detected as 5 consecutive black dots and step 215 is Y, then "ADC=ADC" is detected as in steps 221 to 223.
+1" 231 to "Black?" 233 are executed, and while step 233 is Y, "BCT=" is executed as in step 214.
BCT + 1” 234 and start mark 5
_3. Count the number of consecutive black dots corresponding to the width x of 531, and as the start mark ₅₃₁ ends and step 233 becomes N, "PR=ADC-
(BCT/2)-(4+2)"241, the 6th
Find the reference position P _R in Figures and Figure 8.

In other words, the address counter ADC at this time
indicates address A ₆ in Figure 8, and black counter BCT
indicates the width x of the start mark 53 ₁ ,
The center position P _C is determined by BCT・(1/2), and by subtracting 1/2 of the original start mark 53 ₁ width W and (4+2) dots corresponding to the tolerance, the center position P C corresponds to the reference position P _R. Address A _R in memory is found.

Therefore, the address obtained by step 241
The ID marks 53 ₁ to 55 ₂ can be read accurately by reading out the memory based on _AR and determining whether it is black or white depending on the content of each address.

However, in the calculation of step 241, (4+2) in the third term on the right side may be determined according to the specific width W of the start mark ₅₃₁ and the tolerance, and the tolerance may be omitted depending on the conditions. .

Further, in checking the number of consecutive dots in step 215, the number of consecutive dots may be selected depending on the situation other than 5 dots or more, and the same applies even if the process of FIG. 1 is performed simultaneously with reading.

In addition, MCT41 and SCT42 are integrated,
Alternatively, the same effect can be achieved by using a dedicated control circuit, and the SPM27 can be used in addition to a step motor.
Various motors can be used as long as the transfer amount can be predicted, and not only horizontal printers but also
Various modifications are possible, such as being applicable to various types of printers.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the ID mark can be accurately read even if the paper is inserted in an irregular manner when reading the ID mark, and therefore, various types of printers that read the ID mark can use the present invention. Remarkable effects can be obtained.

[Brief explanation of drawings]

The figures show an embodiment of the present invention; FIG. 1 is a flowchart for checking the reference position, FIG. 2 is a side view showing the main parts, and FIG. 3 is a cutaway perspective view of the main parts showing the support situation of the printing bed. Figure 4 is a perspective view showing how the ID sensor is installed, Figure 5 is a block diagram of the circuit configuration,
Figure 6 is a diagram showing the recording status and installation status of the ID mark, Figure 7 is a diagram showing the detection status of the ID mark,
FIG. 8 is an enlarged view of the situation in which the reference position is determined, FIG. 9 is a flowchart of the reference position determination situation, and FIG. 10 is a diagram for explaining the determination start timing. 14...Print head (PHD), 27...Motor (SPM), 37...IDS (ID sensor), 41...Main control section (MCT), 42...Sub control section (SCT), 5
1...Paper, 53 ₁ to 55 ₂ ...ID mark, P _R ...
Reference position, P...Pitch, W...Specific width, P _c ...
center position.

Claims (1)

[Scope of Claims] 1. In a printer that reads identification marks on a sheet of paper, each consisting of a plurality of marks each having a specific width, recorded at a predetermined pitch in the form of a barcode in the row direction of the paper, in a fixed direction from a reference position. , photoelectrically read each of the marks in a certain direction to detect the first mark, find the width of the mark, multiply the value of the width by 1/2 to calculate the center position, and calculate the specified position from the center position. A method for reading an identification mark for a printer, characterized in that the reference position is obtained by subtracting 1/2 of the width, and the identification mark is read at predetermined intervals using the reference position as a reference.