JP4545294B2 - 2-color printer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a two-color printer having a function of printing characters and the like in two colors on an object to be printed such as paper or a label. In the present application, the act of forming not only characters but also images such as symbols and figures on a printed material is referred to as printing.
[0002]
[Prior art]
In recent years, two-color printers having a function of performing two-color printing on a printing object have been commercialized. For example, Japanese Patent Application Publication (JP-A) No. 61-192568 discloses a two-color printer provided with a memory having two drawing buffer areas of the same size for storing print data of two colors separately. ing. This two-color printer performs two-color printing by repeating the process of alternately reading one line of data from each drawing buffer area and alternately printing each color on one line of the substrate.
[0003]
[Problems to be solved by the invention]
However, since the two-color printer disclosed in the above publication uses a dedicated buffer area for each color, it requires twice as much memory capacity as a single-color printer.
SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a two-color printer that can achieve two-color printing of the same level as a conventional one using a minimum memory capacity.
[0004]
[Means for Solving the Problems]
In order to solve the above problems, a printer according to the present invention includes a drawing buffer area in which a plurality of memory cells are arranged vertically and horizontally, a vertical status buffer area for storing a vertical status for each vertical column of the drawing buffer area, and a drawing buffer. Prints an image according to the print data on the two-color thermal paper that is the printing object in at least one of the two colors, the memory that contains the horizontal status buffer area that stores the horizontal status for each horizontal row of the area A two-color printer comprising: a print head capable of printing; and a control means for controlling a print operation of the print head by specifying a color determined by a combination of a vertical status and a horizontal status, and a vertical status buffer area Is divided into a plurality of vertical status storage units having a capacity of 8 bits, and “0” or “1” is assigned to each bit of each vertical status storage unit. By setting, the vertical status for each vertical column of the drawing buffer area is stored, and the horizontal status buffer area is divided into a plurality of horizontal status storage units having a capacity of 8 bits. By setting “0” or “1” for each bit, the horizontal status for each horizontal row in the drawing buffer area is stored, and further, all the printing parts in the horizontal first row of the printing object are stored by the control means. Printing is performed with one color, and then the printing portion of the other color in the first horizontal row is reprinted with the other color.
[0005]
In the present invention, print data is stored in one drawing buffer area regardless of the color difference, and is determined by the combination of the vertical status stored in the vertical status buffer area and the horizontal status stored in the horizontal status buffer area. Print the substrate with a color pattern. Therefore, it is possible to achieve both single color printing and two color printing using one drawing buffer area. Therefore, according to the present invention, it is possible to achieve the same two-color printing as the conventional one using the same memory capacity as that of the single-color printer.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a diagram showing the internal structure of a two-color printer according to an embodiment of the present invention.
In the present embodiment, a thermal printer for printing on a label will be described as an example.
A continuous label 13 is wound around a rotatable supply shaft 14 of the thermal printer 10. The label continuous body 13 is configured by temporarily attaching the label 11 to the mount 12 so as to be peeled off. The label 11 is a two-color thermal paper capable of developing red and black. For example, the label 11 develops black at a second temperature higher than the first temperature under a layer that develops red at the first temperature. It is configured by stacking layers.
[0007]
When the stepping motor 16 drives the platen roller 15 via the belt 17, the mount 12 is conveyed from right to left. The conveyance of the mount 12 is controlled based on the detection result of the sensor 19, and the label 11 is printed by the thermal head 18. The operation of each unit is controlled by the control unit 20.
In the present embodiment, the head width of the thermal head 18 is set to 108 mm, and printing for a maximum of 864 dots can be performed at a time. The printing range in the length direction of the label 11 (perpendicular to the longitudinal direction of the thermal head 18) is set to 400 mm at the maximum, and printing for a maximum of 3200 lines on one label 11 is possible.
[0008]
FIG. 2 is a block diagram of the control unit 20 that controls each unit of the thermal printer 10.
In a ROM (read only memory) 21 of the control unit 20, a control program for the operation of each unit is stored in advance. On the other hand, RAM (random access memory) 22 temporarily stores various data such as print data and setting data. These data are supplied from the computer 28 to the RAM 22 via the external interface 27, for example. Each unit of the control unit 20 operates when power is supplied from the power supply unit 40.
[0009]
FIG. 3 is a diagram showing the division of the memory area of the RAM 22.
Most of the memory area of the RAM 22 is used as the drawing buffer area 30, and the remaining part is used as the vertical status buffer area 31 and the horizontal status buffer area 32.
In the drawing buffer area 30, a plurality of memory cells having a 1-bit capacity are arranged vertically and horizontally, and an image to be printed on the label 11 is stored as print data “1”. In the present embodiment, since the number of horizontal dots in the drawing buffer area 30 is 864 dots and the number of vertical lines in the drawing buffer area 30 is 3200 lines, the capacity of the drawing buffer area 30 is 345,600 bytes (337). .5 kilobytes, where 1 kilobyte = 1024 bytes). The capacity of the vertical status buffer area 31 is 864 bytes, and the capacity of the horizontal status buffer area 32 is 3200 bytes.
[0010]
FIG. 4 is a diagram showing the division of the vertical status buffer area 31.
The vertical status buffer area 31 is divided into vertical status storage units D (1) to D (864) that store the vertical status for each vertical column of the drawing buffer area 30. In the present embodiment, the vertical status storage unit D (1) has a capacity of 8 bits (1 byte), and by setting each bit to “0” or “1”, the drawing buffer area 31 The vertical status of the first vertical column (first dot) is stored. This vertical status is used to specify the color of each print data of the first dot in the drawing buffer area 30. The same applies to the remaining vertical status storage units D (2) to D (864).
[0011]
FIG. 5 is a diagram showing the division of the horizontal status buffer area 32.
The horizontal status buffer area 32 is divided into horizontal status storage units L (1) to L (3200) that store the horizontal status for each horizontal row of the drawing buffer area 30. In this embodiment, the horizontal status storage unit L (1) has a capacity of 8 bits (1 byte), and by setting each bit to “0” or “1”, the drawing buffer area 31 The horizontal status of the first horizontal row (first line) is stored.
This horizontal status is used to specify the color of each print data on the first line in the drawing buffer area 30. The same applies to the remaining horizontal status storage units L (2) to L (3200).
[0012]
FIG. 6 is a diagram for explaining a method for specifying the color of print data according to the present embodiment. In FIG. 6, for the sake of simplicity, the number of horizontal dots and the number of vertical lines are shown smaller than those in FIG.
In the vertical status buffer area 31, “1” is set in the second bit (bit 1) of the vertical status storage units D (3) to D (6), and the vertical status storage units D (13) to D (D). “1” is set in the first and second bits (bit 0 and bit 1) of (16). On the other hand, in the horizontal status buffer area 32, “1” is set to the first bit (bit 0) of the horizontal status storage units L (3) to L (7), and the horizontal status storage unit L (17). “1” is set in the second bit (bit 1) of .about.L (21).
[0013]
In this embodiment, when the vertical status and horizontal status of print data “1” are compared, if the bit number set with “1” is different, the print data “1” is designated as red print data. When the bit numbers set with “1” are equal, the print data “1” is designated as black print data. According to such a designation method, for example, in the vertical status and horizontal status of the print data “1”, the logical value “1” is obtained when the bit numbers set with “1” are equal, and in other cases The color information is reproduced by using a logical operation that can obtain a logical value “0”.
[0014]
Referring to FIG. 6, for example, the print data “1” at the position (D (3), L (4)) belonging to area A1 has a vertical status in which “1” is set in the second bit, and 1 It has a horizontal status with the first bit set to "1". As described above, in the areas A1 and A4 of the drawing buffer area 30, there is no print data “1” having the vertical status and the horizontal status with the same bit number set to “1”. Accordingly, all print data “1” belonging to areas A1 and A4 is designated as red print data.
[0015]
On the other hand, for example, the print data “1” at the position (D (13), L (4)) belonging to the area A4 has a vertical status and a horizontal status in which “1” is set in the first bit. Yes. As described above, in the areas A2, A3, and A5 of the drawing buffer area 30, all the print data “1” has the vertical status and the horizontal status in which “1” is set to the same bit number. Accordingly, all print data “1” belonging to areas A2, A3, and A5 is designated as black print data.
[0016]
Note that the capacity of the vertical status storage unit and horizontal status storage unit may be 16 bits (1 word) instead of 8 bits (1 byte). In this case, the color of the print data stored in the drawing buffer area can be specified in detail, but the capacity required for the vertical status buffer area and the horizontal status buffer area is twice that of this embodiment.
[0017]
Again, the control part 20 is demonstrated, referring FIG.
A CPU (central processing unit) 23 of the control unit 20 controls the motor control unit 24, the sensor control unit 25, and the thermal head control unit 26 in accordance with a control program stored in the ROM 21. Under the control of the CPU 23, the motor control unit 24 operates the stepping motor 16, and the sensor control unit 25 operates the sensor 19.
[0018]
The thermal head control unit 26 drives the thermal head 18 based on various data stored in the RAM 22 under the control of the CPU 23. More specifically, in the red printing mode, the thermal head control unit 26 supplies a first power amount (for example, 0.2 mJ) to each heating element of the thermal head 18. In this way, the label 11 is printed in red by heating the printing portion of the first line of the label 11 to the red coloring temperature.
[0019]
In the black printing mode, the thermal head control unit 26 supplies a second power amount (for example, 0.5 mJ) larger than the first power amount to each heating element of the thermal head 18. In this case, the heating temperature of the thermal head 18 is higher than that in the case of red printing. In this way, the label 11 is printed in black by heating the black printing portion of the first line of the label 11 to the black coloring temperature.
[0020]
FIG. 7 is a timing chart showing the operation timing of two-color printing in the thermal printer 10. Two-color printing according to the present embodiment is performed in the following order.
First, the print data of the first line in the drawing buffer area 30 is transferred to the thermal head 18 as it is for red printing. By stopping the latch clock, fixing the print data, and setting the strobe signal to the high level, the thermal head 18 prints all the print portions of the first line of the label 11 in red.
[0021]
Next, only black print data is extracted from the print data of the first line in the drawing buffer area 30 and transferred to the thermal head 18. In the present embodiment, for example, whether or not the print data is black print data can be determined by the logical product of the logical values set in the same number bits of the vertical status and horizontal status of the print data “1”. Only black print data can be extracted from one line of print data.
By stopping the latch clock, fixing the print data, and setting the strobe signal to the high level, the thermal head 18 prints the black print portion of the first line of the label 11 in black.
Note that the print data of the second line in the drawing buffer area 30 may start to be transferred to the thermal head 18 in synchronization with the end of the black printing. At that time, by driving the stepping motor 16, the mount 12 is conveyed so that the second line of the label 11 comes to the printing position of the thermal head 18, and the same operation is repeated for the second and subsequent lines of the label 11. The label 11 is printed in two colors.
[0022]
As described above, in the present embodiment, print data is stored in one drawing buffer area 30 regardless of the color difference, and is stored in the vertical status stored in the vertical status buffer area 31 and in the horizontal status buffer area 32. The label 11 is printed in a color pattern determined by the combination with the horizontal status. For this reason, both single color printing and two color printing can be achieved by one drawing buffer area 30. Therefore, according to the present embodiment, by using the RAM 22 having the same capacity as that of the single-color printer, it is possible to achieve the same two-color printing as the conventional one.
[0023]
In this embodiment, there is a possibility that the processing time may be increased when performing monochromatic printing on the entire surface of the label. In this case, for example, a function capable of designating one of red printing and black printing on a thermal printer is provided. By giving, such a malfunction can be avoided.
[0024]
【The invention's effect】
As described above, according to the present invention, it is possible to achieve two-color printing of the same level as the conventional one using the minimum necessary memory capacity.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a main configuration of a two-color printer according to an embodiment of the present invention.
FIG. 2 is a block diagram of a control unit that controls each unit of the two-color printer of FIG. 1;
FIG. 3 is a diagram showing main divisions of a memory area of the RAM shown in FIG. 2;
4 is a diagram showing a division of a vertical status buffer area shown in FIG. 3. FIG.
FIG. 5 is a diagram showing a division of a horizontal status buffer area shown in FIG. 3;
6 is a diagram illustrating a method for specifying the color of print data in the two-color printer of FIG. 1; FIG.
7 is a timing chart illustrating the operation timing of two-color printing in the two-color printer of FIG.
[Explanation of symbols]
10 Thermal Printer 11 Label 18 Thermal Head 20 Control Unit 22 RAM
26 thermal head control unit 30 drawing buffer area 31 vertical status buffer area 32 horizontal status buffer areas D (1) to D (864) vertical status storage sections L (1) to L (3200) horizontal status storage section

Claims (3)

A drawing buffer area in which a plurality of memory cells are arranged vertically and horizontally, a vertical status buffer area for storing a vertical status for each vertical column of the drawing buffer area, and a horizontal status for each horizontal line of the drawing buffer area are stored. Memory including horizontal status buffer area;
A print head capable of printing an image in accordance with print data on two-color thermal paper , which is a print object , in at least one of the two colors ;
Control means for controlling a printing operation of the print head by designating a color determined by a combination of the vertical status and the horizontal status;
A two-color printer comprising :
The vertical status buffer area is divided into a plurality of vertical status storage units having a capacity of 8 bits,
By setting “0” or “1” for each bit of each vertical status storage unit, the vertical status for each vertical column of the drawing buffer area is stored,
The horizontal status buffer area is divided into a plurality of horizontal status storage units having a capacity of 8 bits,
By setting “0” or “1” for each bit of each horizontal status storage unit, the horizontal status for each horizontal row of the drawing buffer area is stored,
Further, the control means prints all the printed portions in the first horizontal row of the substrate to be printed in one color, and then reprints the printed portion in the second horizontal row in the other color in the other color. A two-color printer characterized by the above. The two-color printer according to claim 1, further comprising a function capable of specifying one of printing in red and black printing when monochromatic printing the printing object. 2. The print object according to claim 1, wherein a layer that develops color at a first temperature and a layer that develops color at a second temperature higher than the first temperature are laminated below the layer. 2. The two-color printer described in 2.

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