JPH06979A - Printer device - Google Patents

Abstract

PURPOSE:To ensure that print irregularities between printing heads can be automatically adjusted when a dot impact-type printer having printing heads is used. CONSTITUTION:The chromatic concentration of a printed character varies according to each printing head, when printing is performed using printing heads 11, 12, 13. A means 110 for adjusting print uneveness is for eliminating these uneveness. A black mark is printed for each printing head on a printing sheet by activating the means 110, and is read using mark sensors 31, 32. Thus the chromatic concentration of the black mark is examined, so that an energization time setting value is low for a printing head which prints the black mark of high chromatic concentration, and is high for a printing head which prints the black mark of low chromatic concentration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is an impact type dot printer having a plurality of print heads and is capable of automatically adjusting unevenness in shade between the plurality of print heads.

[0002]

2. Description of the Related Art When a character is printed on a copy sheet by an impact type dot printer having a plurality of print heads, the shade of the character printed on the lowermost sheet may be different for each print head. In order to eliminate the unevenness of printed characters on each print head on the lowest paper, the print head mounting method can be changed to adjust the distance between the print head and the paper surface, and the energization time for the print pin drive coil can be changed. , It is replaced with a print head with different characteristics.

FIG. 6 is a view for explaining the adjustment of the mounting of the head. In the figure, 11 to 13 are print heads,
Each CR indicates a carrier. Three print heads 11, 12, and 13 are fixed to the carrier CR. The carrier CR moves left and right. Each print head is of the dot impact type and has multiple print pins.
And a print pin drive coil for driving each print pin.

As described above, when printing is performed on a copy sheet with this type of printer device, the darkness of the characters printed on the lowest copy sheet may differ from print head to print head.
In such a case, for a print head that prints dark characters, the attachment state of the print head to the carrier is adjusted so that the distance between the print head and the copy sheet becomes long. Further, for a print head on which thin characters are printed, the mounting state of the print head on the carrier is adjusted so that the distance between the print head and the copy sheet becomes short.

FIG. 7 is a diagram for explaining the adjustment of the energization time. When the energization signal rises from low level to high level,
The drive voltage V also rises, and when the energization signal falls from the high level to the low level, the drive voltage V also falls. The longer the high level of the energization signal, the greater the impact force of the print pin on the copy sheet. Therefore, for a print head that prints dark characters, the energization time for the print pin drive coil is adjusted to be short. Further, for a print head on which light characters are printed, adjustment is made so that the energization time for the print pin drive coil is extended. The energization time can be easily adjusted by using a counter. For example, when the print start pulse is received, the energization signal is set to high level and the counter is operated, and when the counter value reaches the energization time set value (set in the register), the energization signal is set to low level.

[0006]

As described above, there are various methods for adjusting the shading unevenness between the print heads, such as adjusting the mounting state of the heads and adjusting the energization time.
In the past, all steps were performed manually, so there was the problem of being extremely complicated. The present invention has been made in view of this point, and in an impact type dot printer having a plurality of print heads, uneven density between print heads due to print head mounting errors and variations in characteristics is automatically generated. It is intended to be adjusted.

[0007]

FIG. 1 is a diagram for explaining the principle of the present invention. As shown in the figure, the printer device of the present invention includes a plurality of dot impact type print heads (11, 12, 13) attached to a carrier (CR) and marks attached to the carrier (CR). A printer device comprising a sensor (31, 32) and a printer control section (100) having a print unevenness adjustment processing means (110), the print unevenness adjustment processing means
(110) performs the process for printing the black mark on each paper for each print head, and the process for reading the black mark on the paper with the mark sensor.If the read black circle is thin, It is configured to increase the energization time for the print head that prints the black circles, and to reduce the energization time for the print head that prints the black circles when the read black circles are dark. It is characterized by that.

[0008]

When the paper is set in the printer and the predetermined switch is pressed after the print unevenness adjustment processing means (110) is activated, the print unevenness adjustment processing means (110) causes the black A process for printing the mark on the paper is performed, and a process for ejecting the paper is performed after the black mark is printed. When this paper is set in the printer device and a predetermined switch is pressed, the print unevenness adjustment processing unit performs processing for reading the black mark on the paper by the mark sensor and determines the darkness of the read black mark. Find out. Then, for the print head on which the dark black mark is printed, the energization time to the print head is set to be short, and for the print head on which the thin black mark is printed, the energization time to the print head is set to be long.

[0009]

FIG. 2 is a diagram for explaining printing and reading in the present invention. In the figure, 11 to 13 are print heads, 31 and 32 are mark sensors, and CR is a carrier. Three print heads 11, 12, and 13 are attached to the carrier CR. Each print head is a dot impact type. Also,
The mark sensors 31 and 32 are also attached to the carrier CR.

In the illustrated example, the leftmost black circle on the paper is printed by the print head 11, the middle black circle is printed by the print head 12, and the rightmost black circle is printed by the print head 13. The leftmost black circle on the paper can be read by the mark sensor 31, and the middle black circle and the rightmost black circle can be read by the mark sensor 32.

FIG. 3 is a diagram showing an example of the output of the mark sensor. In the illustrated example, the leftmost black circle in FIG. 2 has the largest output when read by the mark sensor, and the middle black circle has the next largest output when the mark sensor reads, and the rightmost one. The output when reading a black circle with a mark sensor is the smallest. In such a case, the energization time for the print head 11 is shortened and the energization time for the print head 13 is lengthened.

FIG. 4 is a diagram showing a system configuration example of the present invention. In the figure, 11 to 13 are print heads and 2
1 is a carrier motor, 22 is various motors, 31 and 32
Is a mark sensor, 40 is an adjustment panel, 51 is a hammer driver, 52 is a motor driver, and 53 is a sensor driver.
Driver, 61 is an output port, 62 is an input port, 71
Is a program storage ROM, 72 is a data storage RAM, 8
Reference numeral 0 indicates a CPU, and 90 indicates an address decoder.

The print heads 11 to 13 are of the dot impact type. The carrier motor 21 moves the carrier. Various motors mean a line feed motor, a paper feed motor, and the like. The mark sensors 31 and 32 are attached to the carrier and read the marks on the paper. The adjustment panel 40 is used when adjusting the unevenness of light and shade between the print heads, and has a liquid crystal panel and various keys.

The hammer driver 51 has an output port 61.
The signal sent from the device is converted into a signal for driving the print pin drive coil. In the hammer driver 51, there is a circuit that controls the energization time. The motor driver 52 converts the signal sent from the output port 61 into a signal for driving the motor. The sensor driver 53 amplifies the analog signal sent from the mark sensors 31 and 32 and converts it into a digital signal. The output of the sensor driver 53 is sent to the input port 62.

The output port 61 is for outputting a signal on the data bus to the outside, and the input port is for putting a signal from the outside on the data bus. Various programs are stored in the program storage ROM 71,
The data storage RAM 72 stores temporary data. The CPU 80 executes the program stored in the program storage ROM. Address decoder 90
Decodes the address on the address bus to select the output port 61, the input port 62, the program storage ROM 71, or the data storage RAM 72.

FIG. 5 is a diagram showing a processing flow of the present invention. A program for adjusting print unevenness is stored in the program storage ROM. When this program is started,
The following processing is performed. When activated, the print unevenness adjusting program displays "Set copy single-cut sheet in hopper" on the liquid crystal panel. In step S1,
According to this instruction, the operator sets the copy cut sheet in the hopper. When the operation of step S1 is performed, a display saying "press start switch" is displayed on the liquid crystal panel. In step S2, the operator depresses the start switch according to this instruction.

In step S3, the sheet is sucked from the hopper. In step S4, a black circle is printed for each head. In step S5, the paper is discharged to the stacker.

When the processing of step S5 is performed, a display saying "set only the lowest paper" is displayed on the liquid crystal panel. In step S6, the operator sets only the lowest copy paper in the hopper according to this instruction. When the operation of step S6 is performed, "Start /
The message "Press switch" is displayed. In step S7, the operator presses the start switch according to this instruction.

In step S8, the sheet is sucked from the hopper. In step S9, the printed black circle is read.
In step S10, the reflectance (darkness) of the black circles printed by each head is analyzed. The darkness of the black circle printed by the head 1 is D1, the darkness of the black circle printed by the head 2 is D2, and the darkness of the black circle printed by the head 3 is D3. If the difference between D1, D2, and D3 is within Dx, the process is ended. If not, the process proceeds to step S11. Note that the energization time information at the end of the process is stored in the nonvolatile RAM.
Etc. The energization time information of the nonvolatile RAM is set in the energization time setting register at the start of printing.

In step S11, the energization time of the dark head is shortened and the energization time of the thin head is lengthened in order to match the head of an intermediate density, and then the process returns to step S1. An example of adjusting the energization time will be described. D1>D2> D3
Suppose Further, the energization time of the head 1 is T1, the energization time of the head 1 is T2, and the energization time of the head 3 is T3. In such a case, the new energization time of the head 1 is (D2 / D1) × correction coefficient × T1 The new energization time of the head 3 is (D2 / D3) × correction coefficient × T3. Information indicating the energization time is stored in the data storage RAM and the energization time setting register.

[0021]

As is apparent from the above description, the printer device of the present invention analyzes the darkness of black circles printed on paper by a plurality of printheads, and energizes the printheads according to the darkness of the black circles. Since the time is adjusted, it is possible to easily adjust the shading unevenness between a plurality of print heads.

[Brief description of drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a diagram illustrating printing and reading in the present invention.

FIG. 3 is a diagram showing an example of a mark sensor output.

FIG. 4 is a diagram showing a system configuration example of the present invention.

FIG. 5 is a diagram showing a processing flow of the present invention.

FIG. 6 is a diagram illustrating adjustment of head attachment.

FIG. 7 is a diagram illustrating adjustment of energization time.

[Explanation of symbols]

 11 print head 12 print head 13 print head 21 carrier motor 22 various motors 31 mark sensor 32 mark sensor 40 adjustment panel 51 hammer driver 52 motor driver 53 sensor driver 61 output port 62 input port 71 program storage ROM 72 data storage RAM 80 CPU 90 address decoder

Claims (1)

[Claims] 1. A dot attached to a carrier (CR)
Multiple impact type print heads (11, 12, 13) and mark sensor (31, 32) mounted on the carrier (CR)
And the printer control unit (10) having the print unevenness adjustment processing means (110).
0) and the print unevenness adjustment processing means (110) performs processing for printing black marks for each print head on the paper, and marks the black marks on the paper. If the read black circle is thin, the sensor is read, and the energization time for the print head that printed the black circle is extended.If the read black circle is dark, the print head that printed the black circle is printed. A printer device, which is configured to perform a process for shortening the energization time to the printer.