JPH0554165A - Method for printing bar code - Google Patents

Abstract

PURPOSE:To print a bar code without lowering a reading rate by printign a black bar with a certain number of dot trains obtd. by subtracting a set number from the number of basic dot trains in the black bar, and forming a white bar with a certain number of dot trains obtd. by adding the set number to the number of basic dot trains in the white bar. CONSTITUTION:In the case of printing the bar doce, the number of the basic dot tranins in the black bar is calcuated from required width LB of the black bar and the diameter of a printing wire, and the black bar is printed with a certain number of dot trains obtd. by subtracting the set number from the number of dot trains in the black bar. The number of basic dot trains in the white bar is calculated from required width LW of the white bar and the diameter of a printing wire, and the white bar is formed with a certain number of dot tranins obtd. by adding the set number to the number of basic dot trains in the white bar. In the case of printing the white bar and the black bar having the same width, the white/black bar ratio of the printed result is set to almost 1:1, the number of dot trains in the fine white bar is set to 4, and the number of dot trains in the fine black bar is set to 2. As the result, the reading rate can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for printing a bar code by a wire dot printer.

[0002]

2. Description of the Related Art Conventionally, bar code printing has been performed by using a bar code printer such as letterpress printing or offset printing to ensure high-resolution printing so that reading by a bar code reader can be reliably performed. There is. However, as the performance of bar code readers has improved, it becomes possible to read even low density bar codes, and printing with a general-purpose wire dot printer has become possible. In this case, the message data and the barcode can be continuously printed on the same printing surface, so that the usage of the barcode can be expanded.

In this case, in the print head of the wire dot printer, an armature having a print wire fixed to the tip thereof is swingably supported by a leaf spring, and the armature is attracted to the core by the magnetic flux generated by the permanent magnet. Then, an exciting current is passed through the coil wound around the core to demagnetize the magnetic flux to release the armature from the core.

The print wire at the tip of the armature flies and hits the print medium on the platen via the ink ribbon to print. By the way, the barcodes are classified according to the thicknesses of the black bar and the white bar that constitute them. One is a JAN code, and this kind of barcode is composed of a black bar and a white bar consisting of basic elements of a predetermined width, and the basic elements are adjacent to each other to form black bars and white bars of various thicknesses. It is supposed to do. In this case, a data length of 12 is called a JAN standard code, and a data length of 6 is called a JAN short code.

The other is to represent a bar code by combining a black bar and a white bar of two types of thickness. In this case, the data length can be set arbitrarily without restriction. When a bar code is printed using the above wire dot printer, when forming a black bar and a white bar having the same thickness, the same number of dot rows are conventionally assigned to the white bar and the black bar.

FIG. 2 is a diagram showing a printing example in a conventional bar code printing method. In the figure, a plurality of vertical lines indicate positions where dots can be printed, and the distance between the vertical lines is 1/180 inch (= 0.1411 mm),
The circles on the vertical lines are the dots to be printed (dot diameter φ0.2m
m) is shown. In the case of the above barcode printing method, 180
In a dot matrix of dots / inch, dots having a diameter of 0.2 mm are used, the black thin bar has a 3-dot row configuration (0.4422 mm), and the white thin bar also has a 3-dot row configuration (0.3644 mm).

[0007]

However, in the above-described conventional bar code printing method, since the wire dot printer is used for printing, the amount of ink bleeding may vary depending on the ink remaining amount of the ink ribbon and the surface condition of the print medium. The dot diameter may change and the white / black bar ratio may become incorrect.

FIG. 3 is a diagram showing an example of printing when ink bleeding occurs in the conventional barcode printing method. Although printed under the same conditions as in FIG. 2, the diameter of the printing wire is φ0.2 mm, whereas the dot diameter is increased to φ0.3 mm due to ink bleeding. In this case, the width of the black thin bar is 0.5822 mm and the width of the white thin bar is 0.2644 mm. That is, white /
The black bar ratio is 1: 1.2 in FIG. 2, whereas it is 1: 2.2 in FIG. As a result, not only does it deviate from the permissible dimensional standard determined for each bar code type, but it also reduces the reading rate of the printed bar code when actually used.

FIG. 4 is a diagram showing another example of printing in the conventional barcode printing method, and FIG. 5 is a diagram showing changes in the printing state with time in the conventional barcode printing method. In the example shown in FIG. 4, the distance between the vertical lines is 1
Although it is / 144 inch, the position where dots can be printed is on the vertical line arranged every 1/72 inch. Further, the distance between a plurality of horizontal lines is 1/144 inch, and dots can be printed on each horizontal line. The diameter of the printing wire in this case is φ0.3
It is 5 mm.

When printing is performed under the above conditions, the widths of the thin black bars and the thin white bars change as shown in FIG. In FIG. 5, the printing time is represented by the number of printed dots. As shown in the figure, it can be seen that the width of the black thin bar becomes gradually narrower and the width of the white thin bar becomes thicker as time passes.
The present invention solves the problems of the conventional barcode printing method described above, and when reading a printed barcode, the amount of ink bleeding changes depending on the ink remaining amount of the ink ribbon and the state of the surface of the print medium. An object of the present invention is to provide a bar code printing method that does not reduce the reading rate.

[0011]

Therefore, in the barcode printing method of the present invention, a wire dot printer is used, the printing wire is ejected, and the printing medium on the platen is hit through the ink ribbon. To form a black bar and a white bar. Then, determine the number of basic dot rows of the black bar from the required width of the black bar and the diameter of the printing wire, and print the black bar with the number of dot rows that is the number of basic dot rows of this black bar minus the set number. To do. In addition, the number of basic dot rows of the white bar is calculated from the required width of the white bar and the diameter of the printing wire, and the white bar is formed by the number of dot rows obtained by adding the set number to the number of basic dot rows of the white bar. To do.

The wire dot printer is connected to a host device, and only when a bar code print instruction command defining bar code data is received from the host device.
Change the dot row. When receiving image data from the host device and printing a barcode, the dot column is changed in the host device. The total print dot number may be detected and stored in the non-volatile memory, and the dot row may be changed when the total print dot number exceeds the set value. Further, the bar width of the printed bar code may be detected, the bar width may be compared with a reference value, and the dot row may be changed only when the bar width needs to be corrected.

Further, in a method of printing a bar code forming a black bar and a white bar arranged in a JAN code, in the basic element forming the black bar and the white bar and the basic element obtained from the diameter of the printing wire. , And the number of elements corresponding to the required widths of the black bar and the white bar is N, a black bar is printed with K × N−1 dot rows, and K × N + 1. Form a white bar with a number of dot rows.

[0014]

According to the present invention, the wire dot printer is used as described above, the printing wire is ejected to the platen, and the black bar and the white bar are hit by hitting the printing medium on the platen through the ink ribbon. To form. In this case, the ink ribbon is replaced in a relatively high density state in order to obtain a print density sufficient for identifying the barcode. Therefore, ink bleeding occurs and the white / black bar ratio of the bar code does not reach an appropriate value.

Therefore, the number of basic dot rows of the black bar is obtained from the required width of the black bar and the diameter of the printing wire, and the number of dot rows obtained by subtracting the set number from the number of basic dot rows of the black bar is black. Print the bar and reduce the width of the black bar. Then, the number of basic dot rows of the white bar is obtained from the required width of the white bar and the diameter of the printing wire, and the white bar is formed by the number of dot rows obtained by adding the set number to the number of basic dot rows of the white bar. Then, increase the width of the white bar.

The wire dot printer is connected to a host device, and only when a bar code print instruction command defining bar code data is received from the host device.
Change the dot row. When receiving image data from the host device and printing a barcode, the dot column is changed in the host device. The total print dot number is detected and stored in the non-volatile memory, and when the total print dot number exceeds the set value, the bar width of the printed bar code is detected, and the bar width is compared with the reference value, If you change the above dot row when the bar width needs to be corrected,
The bar width is corrected according to the state of the ink ribbon and the state of the print medium.

Further, in the printing method of the bar code forming the black bar and the white bar arranged in the JAN code, the basic element obtained from the width of the basic element forming the black bar and the white bar and the diameter of the printing wire. , And the number of elements corresponding to the required widths of the black bar and the white bar is N, a black bar is printed with K × N−1 dot rows, and K × N + 1. Form a white bar with a number of dot rows.

In this case, since the dot row is not changed for each basic element and 1 is added to or subtracted from the value of K × N, the dot row is not changed more than necessary.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a diagram showing an example of printing in the barcode printing method of the present invention. In the figure, the vertical lines indicate the positions where dots can be printed.
The distance between each vertical line is 1/180 inch (= 0.1411m
m), and the ∘ mark on the vertical line indicates a dot to be printed.
L _B is the width of the thin black bar, L _W is the width of the thin white bar, L _D
Indicates the printed dot diameter.

In this case, the number of basic dot rows of the black bar is obtained from the required width of the black bar and the diameter of the printing wire, and a set number, for example, 1 is subtracted from the number of basic dot rows of the black bar. Print black bars in columns. Further, the number of basic dot rows of the white bar is obtained from the required width of the white bar and the diameter of the printing wire, and the number of the basic dot rows of the white bar is set by a set number, for example, 1 It is designed to form a bar.

For example, 180 DPI (dots / inch)
When the white dot and the black bar having the same width are printed by using the wire dot printer of No. 3, the number of dot rows is set so that the white / black bar ratio of the print result is approximately 1: 1. That is, the dot row of the thin white bar is set to 4 dots, and the dot row of the black thin bar is set to 2 dots. By the way, in order not to reduce the reading rate of the bar code reader, it is necessary to prevent the PCS value (black-and-white reflection ratio) of the printed bar code from dropping. Therefore, the ink ribbon used in the bar code printing method should be replaced when it is considerably darker (PCS value is around 0.5) than the density limit (PCS value around 0.3 is normal) for normal print output. To be done. Therefore, ink bleeding is always present, and when printing is performed with a diameter of the printing wire of φ0.2 mm, the dot diameter L _D becomes φ0.25 mm to φ0.3 mm. However, by using the dot matrix shown in FIG. 1, the white / black bar ratio is (1: 0.86) to (1: 1.
09), and the reading rate can be improved.

Changing the number of dot rows as described above is limited to the case where a bar code printing instruction command defining bar code data is received from the host device, and bar code printing is performed by receiving image data. In addition, the number of dot rows is changed in the host device, and the wire dot printer can print with the set number of dot rows.

Next, the bar code print instruction command will be described. FIG. 6 is a diagram showing an example of printing by the barcode printing instruction command. (A) of the figure shows the bar part
(B) shows the OCR-B character portion. The bar code print instruction command transmitted from the host device has the following configuration.

[0024]

[Equation 1]

Is a symbol indicating a bar code print instruction command, and n _{1 to} n ₃ are parameters of the bar code print instruction command. n ₁ is the type of barcode (for example, JAN standard, JAN shortening, CODE39, NW-7
Etc.), n ₂ is a bar code printed by a bar as shown in (a) of FIG. 6 or (b)
This is a parameter for deciding whether to print with OCR-B characters as shown in. Further, n ₃ is a parameter for designating the data length, but since the data length is fixed in the JAN code, it is used for designating the flag character indicating the country code. D _{1 to} D _m are
This is bar code data expressed in characters.

When a white / black bar is formed by multiplying a basic element by a plurality of times, as in the JAN code, a calculation formula of a bar-constituting dot row is used to prevent ink bleeding. FIG. 7 is a diagram showing a calculation formula for a bar-constituting dot row. If the number of dot rows of basic elements is K, and the number of dot rows of black bars is simply changed to (K-1), when N elements continue, N (K-1) ) A dot row is formed, and the N dot row becomes a black bar that is thinner than the black bar of the N.K dot row that is originally supposed to be printed, resulting in an abnormal white / black bar ratio.

Therefore, by setting (K.N-1) dots, -1 dot is canceled by ink bleeding to form a K.N dot row. On the other hand, for the white bar, similarly, by setting (K · N + 1) dots,
Due to ink bleeding, +1 dot disappears to form a K · N dot row. In this way, the white / black bar ratio can be properly maintained without affecting the width of the entire bar code.

Next, a case will be described in which the dot row is changed in response to the amount of ink bleeding changing with the passage of time. FIG. 8 is a block circuit diagram of a printer to which the barcode printing method of the second embodiment of the present invention is applied. In the figure, 11 is a CPU for controlling the printer,
Reference numeral 12 is a ROM that stores a control program, a font pattern, and the like, and 13 is a RAM that is used to temporarily store data received from a host device (not shown) and data during program execution. Further, 14 is an I / O port, a print head (not shown), a spacing (SP)
Motor, line feed (LF) motor, operation panel,
An interface, DIP switch 15, etc. are connected. Reference numeral 16 is a bus line for connecting the above-mentioned respective elements to exchange data.

In the printer having the above-described structure, when a bar code print instruction command input from an upper device (not shown) via the interface is received, the printer prints as shown in FIG. 9 as an example. Then, when the operator presses the dip switch 15 in accordance with the remaining amount of ink due to the use of the ink ribbon, the number of dot rows of the black thin bar or the white thin bar is increased.

FIG. 9 is a diagram showing a printing example in the case of printing by the barcode printing method of the second embodiment of the present invention, and FIG. 10 is a printing by the barcode printing method of the third embodiment of the present invention. It is a figure which shows the example of printing in the case. In the figure, (a) shows an example of printing when the ink remaining amount of the ink ribbon is large, (b) shows an example of printing when the remaining ink amount of the ink ribbon is small, and (c) shows printing when correction printing is performed. An example is shown. Both are examples of printing with a 24-pin printing head, and the diameter of the printing wire is φ0.2 mm.

Both the vertical and horizontal lines in the figure indicate the positions where dots can be printed. The distance between each vertical line and the distance between each horizontal line is 1/180 inch, and the ● marks indicate dots to be printed. Also, L _B is the width of the thin black bar,
L _W is the width of the thin white bar, and L _D is the printed dot diameter. In the embodiment of FIG. 9, the dip switch 15 (FIG. 8) is pressed when the ink remaining amount is low, and the number of dot rows of the black thin bar is increased.

That is, when the ink ribbon is new and the remaining amount of ink is large, the dot diameter L of the print result is as shown in (a).
_D is, for example, 0.30 mm. In this case, the dip switch 15 is off and the bar width is not corrected. Then, when the ink remaining amount decreases, the dot diameter L _D becomes φ0.25 mm, the width L _B of the black thin bar becomes thin, and the width L _{w of the} white thin bar becomes large as shown in (b). Also in this case, the dip switch 15 is off and the bar width is not corrected. And the ink ribbon is old,
When the dot diameter L _D of the printing result becomes φ0.20 mm, the dip switch 15 is turned on as shown in (c), and the number of dot rows of the thin black bar is corrected from 3 to 4.

Further, in the embodiment shown in FIG. 10, the DIP switch is depressed when the ink remaining amount is large, and the number of dot rows of the thin white bar is increased.
That is, in FIG.
5 is turned on, and the number of dot rows of the thin white bar is corrected from 3 to 4. In FIGS. 5B and 5C, the dip switch 15 is turned off and the bar width is not corrected.

In the second and third embodiments, one DIP switch 15 is provided, but the number of DIP switches 15 can be increased depending on the target accuracy. Further, in the above-described embodiment, the number of dot rows is corrected by keeping the dot density in the horizontal direction constant, but the number of dot rows and the dot density are corrected by setting the dip switch 15 while making the dot density in the horizontal direction variable. Can be combined to further improve the accuracy of correction. Further, the correction may be performed using an operation panel switch (see Japanese Patent Publication No. 2-10974).

FIG. 11 is a block circuit diagram of a printer to which the barcode printing method of the fourth embodiment of the present invention is applied. In the figure, 11 is a CPU for controlling the printer,
Reference numeral 12 is a ROM that stores a control program, a font pattern, and the like, and 13 is a RAM that is used to temporarily store data received from a host device (not shown) and data during program execution. Further, 14 is an I / O port, which includes a print head (not shown), a spacing motor,
A line feed motor, operation panel, interface, etc. are connected. Reference numeral 16 is a bus line for connecting the above-mentioned respective elements to exchange data. Reference numeral 21 is an EEPROM of a non-volatile memory, which stores the total number of print dots.

FIG. 12 is a flowchart of the barcode printing method according to the fourth embodiment of the present invention. Figure (a) shows E
A flow for storing the total print dot number in the EPROM 21 (FIG. 11) is shown, and a flow for clearing the stored total print dot number is shown in (b). In the case of (a), a specific address A in the EEPROM 21 is printed every time the printing process is performed.
The total number of print dots is stored in. That is, the number of dots to be printed and the content of the address A of the EEPROM 21 are added, and the total number of dots printed is the address A.
Stored in. Then, it is determined whether or not the total number of printed dots exceeds the number of dots D that needs to be corrected, and if it exceeds, the bar width of the black thin bar or the white thin bar is corrected. If it does not exceed the limit, no correction is made. Step S1 The printing process is performed. In step S2, the total number of print dots at address A is updated by adding the number of print dots. Step S3: It is determined whether the total print dot number exceeds the dot number D. If it exceeds, proceed to step S4,
If not exceeded, it ends.

In FIG. 3B, the EEPROM 21
When clearing the total number of print dots at address A, whether to clear the ribbon usage amount by pressing the switch on the operation panel according to a preset combination or by pressing a preset amount Make a decision. Step S11 Press the switch. In step S12, it is determined whether or not the ribbon usage amount is cleared. When clearing, the process proceeds to step S13, and when not clearing, the process ends. In step S13, the number of print dots at the address A of the EEPROM 21 is set to 0.

In each of the above embodiments, the bar width is corrected in one step. However, the bar width may be corrected in multiple steps depending on the size and type of the bar code. Further, a sensor for detecting attachment / detachment of the ink ribbon may be provided to automatically clear the address A of the EEPROM 21 when the ink ribbon cartridge is replaced.

FIG. 13 is a block circuit diagram of a printer to which the barcode printing method of the fifth embodiment of the present invention is applied.
FIG. 14 is a flowchart of the barcode printing method according to the fifth embodiment of the present invention. In the figure, 14 is an I / O port, 61 is a head driver connected to the I / O port 14, 63 is a print head, 64 is a reflective sensor mounted on the carriage unit 65 together with the print head 63, It is connected to the I / O port 14 via an AMP 66 that amplifies a signal. The reflective sensor 64 reads the bar code printed by the print head 63 on the carriage unit 65. The bar width of the read barcode is compared with the reference width, and correction is performed based on the comparison result. According to the fifth embodiment, since the correction can be made according to the states of the ink ribbon and the print medium, highly accurate bar code printing can be performed. In step S21, the signal processing of the barcode sensor is performed. In step S22, the bar width detected by the reflective sensor 64 and input is compared with the reference data. In step S23, it is determined whether the bar width needs to be corrected. If correction is necessary, the process proceeds to step S24, and if not necessary, the process ends. In step S24, the bar width is corrected.

The present invention is not limited to the above embodiments, and various modifications can be made based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0041]

As described above in detail, according to the present invention, the black bar is printed with the number of dot rows obtained by subtracting the set number from the number of basic dot rows corresponding to the required width of the black bar, The white bar is formed by the number of dot rows that is the number of basic dot rows corresponding to the required width of the white bar plus the set number, so even if ink bleeding occurs, the white / black bar ratio can be set to an appropriate value. can do.

The total print dot number is detected and stored in the non-volatile memory, and when the total print dot number exceeds the set value,
When the bar width of the printed bar code is detected, the bar width is compared with a reference value, and the dot row is changed when the bar width needs to be corrected, the state of the ink ribbon, the print medium Since the bar width is corrected in accordance with the above state, it is possible to always obtain an appropriate print result.

Therefore, the reading rate can be improved when reading with a bar code reader.

[Brief description of drawings]

FIG. 1 is a diagram showing a printing example in a barcode printing method of the present invention.

FIG. 2 is a diagram showing a printing example in a conventional barcode printing method.

FIG. 3 is a diagram showing a printing example when ink bleeding occurs in a conventional barcode printing method.

FIG. 4 is a diagram showing another example of printing in the conventional barcode printing method.

FIG. 5 is a diagram showing a change with time of a printing state in a conventional barcode printing method.

FIG. 6 is a diagram showing an example of printing by a barcode printing instruction command.

FIG. 7 is a diagram showing a calculation formula for a bar-constituting dot row.

FIG. 8 is a block circuit diagram of a printer to which the barcode printing method according to the second embodiment of the present invention is applied.

FIG. 9 is a diagram showing a printing example when printing is performed by the barcode printing method according to the second embodiment of the present invention.

FIG. 10 is a diagram showing a printing example when printing is performed by the barcode printing method according to the third embodiment of the present invention.

FIG. 11 is a block circuit diagram of a printer to which the barcode printing method according to the fourth embodiment of the present invention is applied.

FIG. 12 is a flowchart of a barcode printing method according to a fourth embodiment of the present invention.

FIG. 13 is a block circuit diagram of a printer to which the barcode printing method according to the fifth embodiment of the present invention is applied.

FIG. 14 is a flowchart of a barcode printing method according to a fifth embodiment of the present invention.

[Explanation of reference numerals] 11 CPU 15 DIP switch 21 EEPROM 64 Reflective sensor

Claims (5)

[Claims] 1. A method of printing a bar code, wherein a black dot and a white bar are formed by using a wire dot printer to fly a print wire and hitting a print medium on a platen through an ink ribbon. ) Obtain the number of basic dot rows of the black bar from the required width of the black bar and the diameter of the above-mentioned printing wire, and (b) subtract the set number from the number of basic dot rows of the black bar to obtain the black bar. Printing, (c) Obtain the number of basic dot rows of the white bar from the required width of the white bar and the diameter of the printing wire, and (d) Add the set number to the number of basic dot rows of the white bar. A method for printing a barcode, which comprises forming white bars in rows. 2. The method of printing a bar code according to claim 1, wherein the wire dot printer changes the dot row only when a bar code printing instruction command defining bar code data is received from a higher-level device. 3. The method of printing a bar code according to claim 1, wherein the total print dot number is detected and stored in a non-volatile memory, and when the total print dot number exceeds a set value, the dot row is changed. 4. A bar width of a printed bar code is detected,
The bar code printing method according to claim 1, wherein the bar width is compared with a reference value, and the dot row is changed only when the bar width needs to be corrected. 5. A bar code which forms a black bar and a white bar arranged in a JAN code by using a wire dot printer to fly a print wire and hit the print medium on the platen via an ink ribbon. In the printing method of (a), the number of dot rows of the basic elements obtained from the width of the basic elements constituting the black bar and the white bar and the diameter of the printing wire is K, and (b) the required black bar and white bar. When the number of elements corresponding to the width of N is N, (c) a black bar is printed with a dot row of (K × N−1), and (d) a dot row of (K × N + 1) is printed. A method for printing a barcode, which comprises forming a white bar.