JP3369397B2 - Printing device and deviation test pattern printed by this device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a printing apparatus which prints a plurality of images by superimposing them on a sheet, and more particularly to a printing apparatus which is used to form a color image having the colors of these images as color components.

[0002]

2. Description of the Related Art A printing device capable of color printing comprises four printing units for printing using heat-soluble ink ribbons of yellow, magenta, cyan and black, respectively. These printing units form a color image by superposing and printing the color component images of the above-mentioned colors on the paper fed along the paper feed path. Each printing unit has a platen roller that is set at right angles to the paper transport path for feeding the paper, and a thermal print head that is pressed against the paper on the platen roller via a heat-soluble ink ribbon of the corresponding color. Each thermal print head has a plurality of dot heating elements arranged in a line facing the corresponding platen roller, and the dots of the ink of the heat-soluble ink ribbon are formed by these dot heating elements in order to form a color component image of the corresponding color. The ink is melted by heat and the melted ink is pressed against the paper.

In this color printer, four color component images need to be properly overlaid to form a color image. The printing positions of these color component images are relatively displaced due to mechanical factors such as molding and mounting of parts or electrical factors such as control of printing timing. This is observed as "color shift" in which the print dots of each color do not completely overlap the print dots of the other colors. For example, since the mounting accuracy of the thermal print head is limited, it is inevitable that this color shift will occur in the production line. In conventional product inspection, an inspector (operator) prints a deviation test pattern on a color printer, and the deviation test pattern is measured using a microscope or the like in order to measure the relative deviation of the printing positions of the color component images, that is, the error. To check.

FIG. 22 shows the main scanning direction X which is perpendicular to the paper transport path.
FIG. 23 shows a first deviation test pattern printed for measuring the positional deviation in FIG. 23, and FIG. 23 shows a second deviation test pattern printed for measuring the positional deviation in the sub-scanning direction P parallel to the paper transport path. It is a figure. These first
And each of the second deviation test patterns is a black bar 1
1, a yellow bar 12, a magenta bar 13, and a cyan bar 14. Here, the black bar 11 is provided as a reference bar longer than the total length of the other bars 12, 13, and 14, and these bars 12, 13, and 1 are provided.
4 is provided as a bar parallel to the black bar 11 and separated by a predetermined distance D. Bars 11, 12, 13, 1
Reference numeral 4 denotes the first deviation test pattern which extends at right angles in the main scanning direction X, and the second deviation pattern extends at right angles in the sub-scanning direction P. The yellow bar 12, the magenta bar 13, and the cyan bar 14 must be formed at the positions indicated by broken lines in FIGS. 22 and 23 so as to correspond to the predetermined distance D. However, in actual printing, it may be formed at a position indicated by a solid line deviating from this position. Such positional deviation is measured as a difference between the distance between each of the bars 12 to 14 and the bar 11 and the predetermined distance D, and the printing positions of the bars 12, 13, and 14 are printed by the bar 11 so as to eliminate this difference. Adjusted for position.

[0005]

However, the above-mentioned inspection method has a drawback that it is difficult to measure the displacement without using a tool such as a microscope. There is a problem that the use of the microscope increases the burden on the inspector (operator). Further, there is a problem that the adjustment accuracy and the adjustment time of the print position depend on the skill level of the operator.

Therefore, a first object of the present invention is to provide a printer capable of printing a deviation test pattern capable of easily and highly accurately measuring the deviation between the printing positions of a plurality of images superimposed on a sheet. It is in.

A second object of the present invention is to provide a printer capable of automatically eliminating a shift between print positions of a plurality of images superimposed on a sheet by using this deviation test pattern.

[0008] A third object of the present invention is to provide a measurable deviation test pattern a plurality of printing position mutual displacement of the image to be overlaid on the paper easily and highly accurately.

[0009]

The invention according to claim 1 is
Multiple printing units arranged so that images can be printed on top of each other
And these printing units to print images in layers.
And a print control circuit for controlling the
One of these printing units in test mode
The semi-printing unit is controlled to pick up in one deviation measurement direction.
A standard scale with multiple scale bars arranged
Print, and print units other than the standard print unit
It is controlled to slightly decrease from the pitch M in the 1 deviation measurement direction.
Difference scale with scale bars arranged at different pitches N
Print in parallel next to the standard scale,
A bias composed of a reference scale and a difference scale.
From the difference test pattern in the one deviation measurement direction
1 Other printing unit for the printing position of the reference printing unit
Of the printing position of the
Test control circuit that changes the print position according to the measurement results
And a reference scale having a plurality of scale bars arranged at a pitch M in another deviation measuring direction different from the one deviation measuring direction by controlling the reference printing unit,
A printing unit other than the reference printing unit is controlled to print a difference scale having scale bars arranged at a pitch N slightly different from the pitch M in the other deviation measurement direction in parallel adjacent to the reference scale; The deviation of the printing position of the other printing unit with respect to the printing position of the reference printing unit is measured in the other deviation measurement direction from the second deviation test pattern composed of the reference scale and the difference scale, and the other deviation measurement pattern is measured. It has a second test control circuit for changing the printing position of the printing unit according to the measurement result. The invention according to claim 2 is a reference scale having a plurality of scale bars which are printed by one reference printing unit of a plurality of printing units which are arranged so as to print images in an overlapping manner and which are arranged at a pitch M in one deviation measurement direction. A difference scale having scale bars printed in parallel adjacent to the one reference scale by a printing unit other than the one reference printing unit and arranged at a pitch N slightly different from the pitch M in the one deviation measurement direction; The pitch N is made shorter than the pitch M by a predetermined length, and a first detailed scale portion configured by the reference scale and the difference scale, and printed by the reference printing unit and arranged at the pitch M in the one deviation measuring direction. For reference scales with multiple scale bars and printing units other than the 1-reference printing unit Ri is printed in parallel and adjacent to said reference scale the 1
The second detailed scale section is composed of a difference scale having graduation bars arranged at a pitch L longer than the pitch M by the predetermined length in the deviation measuring direction. The invention corresponding to claim 3 is the same as the invention of claim 2,
A reference scale having a plurality of scale bars printed by the one reference printing unit and arranged at the pitch M in the one deviation measurement direction, and printed in parallel by a printing unit other than the one reference printing unit adjacent to the reference scale. The reference scale has a scale bar located at the center and a schematic scale portion composed of scale bars aligned in a straight line.

[0010]

[0011]

[0012]

[0013]

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described below with reference to FIGS. This color printer is used as a printing apparatus that prints a plurality of color component images by superimposing them on a label paper or a tag paper, and forms a color image by these color component images. A label sheet is a sheet in which a plurality of labels are arranged in series as an available area and a gap is provided between two adjacent labels, and a tag sheet is a sheet in which a plurality of tags are arranged in an available area.
It is a sheet of paper on which a mark for printing positioning is printed in advance on the back surface of each tag.

FIG. 1 is a diagram schematically showing the internal structure of the color printer 20. This color printer 20
4 printing units 21Y, 21M, 21C and 21
B, a paper holder 26, a pair of conveyance rollers 27, a paper shortage sensor 28, and a position sensor 29. The paper holder 26 rotatably supports a roll 25 of label paper or tag paper. The pair of conveying rollers 27 pulls out the sheet from the sheet holder 26 and supplies the sheet to the sheet conveying path 23. The printing units 21Y, 21M, 21C, and 21B are arranged at equal intervals on the paper transport path 23 so that the dot printing lines are parallel to each other, and the yellow, magenta, cyan, and black color component images are transferred to the paper transport path 23. A color image is formed by superposing and printing on one usable area of the paper fed along the path 23.

The paper-out sensor 28 is used to detect a paper-out between the paper holder 26 and the transport roller 27, and is, for example, a light-transmissive type that detects the trailing edge of the paper to identify the paper-out. It is composed of end sensors. The position sensor 29 is connected to the print unit 21.
A light-transmissive gap that is used to detect the position of the usable area of the sheet between B and the conveyance roller 27, and detects the gap to specify the position of the usable area when the label sheet is used, for example. It is composed of a sensor and a light-reflecting mark sensor that detects a mark in order to identify the position of the usable area when the tag paper is used.

The printing units 21Y, 21M, 21C
And 21B have thermal print heads 22Y, 22M, 22C and 22B capable of printing on 6-inch wide paper, platen rollers 24Y, 24M, 24C and 24B, and ribbon magazines 30Y, 30M, 30C and 30B, respectively. The platen rollers 24Y, 24M, 24
C and 24B are set at right angles to the paper transport path 23, and transport rollers 2 are provided to transport the paper to the exit of the paper transport path 23.
Rotate with 7. The ribbon magazines 30Y, 30
M, 30C and 30B respectively contain yellow, magenta, cyan and black heat-soluble ink ribbons, and the printing units 21Y, 21M, 21C and 21
It is removably attached to B.

The thermal print heads 22Y, 22M,
22C and 22B are the ribbon magazines 30 respectively.
The platen roller 24Y, through the heat-soluble ink ribbon fed from Y, 30M, 30C and 30
It is pressed against the sheets on 24M, 24C and 24B.
These thermal print heads 22Y, 22M, 22
Each of C and 22B has a plurality of dot heating elements arranged in a line so as to face the corresponding platen roller, and in order to print the color component image of the corresponding color, the inks of the heat-soluble ink ribbon are heated by these heating elements. It is melted by heat in units of dots that form pixels, and this is pressed onto paper.

FIG. 2 is a diagram showing a control circuit of the color printer 20. This control circuit has a system control unit CT1 and a print control unit CT2 that can operate in parallel simultaneously. The system control unit CT1 includes a color printer 2
0 CPU (central processing unit) that controls the whole 3
1. ROM (read only memory) 32 for storing the control program of the CPU 31 and other fixed data, CPU 3
RAM (ran that temporarily stores the data input / output to / from
dom access memory) 33, input / output port for connecting various peripheral devices to the CPU 31
) 34, a communication interface 35 for receiving print data, print size data, print format data, etc. as control commands from an external host computer, a system bus 36 for transmitting various data and signals, a keyboard 37 operated by an operator, Keyboard 37
Keyboard controller 3 for detecting key signals from
8, a display 39 for displaying the operating state of the color printer 20, a display controller 40 for controlling the display 39, and a communication buffer for temporarily storing various data transferred from the control CT1 to the control CT2. It has a dual port RAM (DP RAM) 41.

The CPU 31 is connected to the system bus 36.
Via the above-mentioned circuit components 32, 33, 34, 3
5, 38, 40, and 41. The display controller 40 is connected to the display 39, and the keyboard controller 38 is connected to the keyboard 37. The keyboard 37 is used for inputting a normal mode setting command, a test mode setting command, numerical data and the like. The RAM 33 has an area for storing dot image data of four color components of yellow, magenta, cyan and black and various print control data.

The print controller CT2 processes the dot image data and print control data temporarily stored in the dual port RAM 41, and the CPU 42,
A ROM 43 for storing a control program of the PU 42, initial print position data, and other fixed data, a RAM 44 for temporarily storing data input / output to / from the CPU 42, and a four-color component transferred from the dual port RAM 41 for each predetermined number of lines. Print buffer 45 for temporarily storing the dot data of the above, a system bus 46 for transmitting various data and signals, the thermal print heads 22Y, 22M,
A head unit 22 composed of 22C and 22B, a head control unit 47 for driving the head unit 22, a feed motor unit 48 for supplying a driving force to the platen rollers 24Y, 24M, 24C, 24B and the transport roller 27,
A ribbon motor unit 49 that supplies a driving force to the ink ribbons 30Y, 30M, 30C, and 30B, a motor control unit 50 that controls the feed motor unit 48 and the ribbon motor unit 49, and correction data set in a test mode is maintained. Non-volatile RAM 51 for temporarily storing the printheads 22B, 22C, 22 from the position sensor 29.
A timer counter 5 for storing the number of first, second, third and fourth sheet conveyance steps determined corresponding to the distances to M and 22Y and counting the number of steps respectively.
2, the paper out sensor 28, the position sensor 2
It has a sensor group SN composed of 0 and other sensors.

The CPU 42 has circuit components 43, 44, 45, 47, 50, 5 via a system bus 46.
1, and 52. The head section 22 is connected to the head control section 47, and the feed motor section 48 and the ribbon motor section 49 are connected to the motor control section 50. The CPU 42 has interrupt terminals connected to the sensor group SN and the timer counter 52, respectively. The feed motor unit 4
8 is the platen rollers 24Y, 24M, 24C, 2
It is composed of a pulse motor for 4B and a pulse motor for the conveying roller 27, and the speeds of these pulse motors can be adjusted. The timer counter 52 counts the number of drive pulses for driving the pulse motor of the feed motor section 48 as the number of sheet carrying steps.

FIG. 3 is a diagram showing the relationship between the head control section 47 and the head section 22 in more detail. Each of the thermal print heads 22Y, 22M, 22C and 22B has, for example, 1280 dot heating elements H1 to H1280 as a plurality of dot heating elements described above, and further, as shown in FIG. It has two 640-bit shift registers SR1 and SR2. The 1st to 640th bits of the shift register SR1 correspond to the dot heating element H.
1 to H640 respectively, the shift register S
The first to 640th bits of R2 are the dot heating element H64
1 to H1280 respectively.

The head control section 47 includes four head controllers 48Y, which are connected to the thermal print heads 22Y, 22M, 22C and 22B, respectively.
It has 48M, 48C and 48B. Each of these head controllers 48Y, 48M, 48C and 48B can directly read the dot data of the corresponding color component for each line from the print buffer 45. The dot data DATA for one line is composed of, for example, 1200 bits, which is smaller than the number of dot heating elements H1 to H1280 in order to change the print position in the main scanning direction X parallel to the dot print line of the print head. .

Each of the head controllers 48Y, 48
M, 48C, and 48B set dot data DATA for one line in the 41st to 1240th bits, which is normally the center of the line buffer, and set dot data "0" representing non-printing on both sides of the center of the line buffer. The control is performed to set the 1st to 40th bits and the 1241st to 1280th bits, which are located at. In this control, the dot data DATA for one line is divided into dot data DATA1 and DATA2, and the necessary number of dot data "0" mentioned above is further divided into dot data DATA1 and DATA2.
And is serially supplied to the shift registers SR1 and SR2 of the corresponding print head together with the shift clock SCK.

The head controllers 48Y, 48M,
48C and 48B are the print heads 22Y, 22M,
In the line buffers 22C and 22B, counters 47Y, 47M for storing the number of shift clocks SCK determined corresponding to the arrangement of one area for storing the dot data DATA for one line and counting the number of clocks are stored.
47C and 47B, respectively, and each output the output enable signal OE after the shift clock SCK is output by the number stored in the corresponding counter. The shift registers SR1 and SR2 store the dot data DATA1 and DATA2 to which the dot data "0" is added while sequentially shifting in response to the shift clock SCK, and output in parallel in response to the output enable signal OE. The dot heating elements H1 to H1280 are selectively driven according to the contents of the 1st to 1280th bits of the line buffer composed of the shift register SR1 and the shift register SR2. The drive voltage for the dot heating elements H1 to H1280 is supplied from the drive voltage terminal VD.

Here, the operation of the above-mentioned color printer 20 in the normal mode will be described. The CPUs 31 and 42 respectively perform initialization processing when the power is turned on. In these initialization processes, for example, the counters 47Y, 4Y
7M, 47C, 47B and timer counter 51
It is initialized by the initial print control data stored in the OM 43. However, when the correction data is stored in the non-volatile RAM 51, the initial print control data is replaced with the print control data created based on these correction data.

This host computer uses the print data,
When the print size data and print format data are supplied to the color printer 20 as control commands, these control commands are sent to the RAM 33 via the communication interface.
Are sequentially stored in. Based on the control command stored in the RAM 31, the CPU 31 performs a process of creating print control data corresponding to the print size data and print format data and dot image data of four color components corresponding to the print data in the RAM 33. CPU 42
The print size and print format are determined based on the print control data created in the RAM 33 and supplied to the dual port RAM 41.
Then, the dot image data of the four color components stored in the dual port RAM 41 is transferred to the print buffer 45 for each predetermined number of lines.

Further, the CPU 42 commands the operations of the timer counter 52 and the head controller 48B in response to the interrupt signal from the position sensor 29. The head controller 48B reads one line of black dot data from the print buffer 45, and outputs the dot data DATA for one line to the dot data DATA1 and DATA.
The data is divided into two, the required number of dot data "0" is added to these dot data DATA1 and DATA2, and the dot data "0" is output to the print head 22B together with the number of shift clocks SCK stored in the counter 47B. Dot data DA
TA1 and DATA2 are the required number of dot data "0" in the shift registers SR1 and SR2 of the print head 22B.
Is stored with. By doing so, the data can be stored in about half the time compared to the case where only one shift register is used, and the printer is suitable for high-speed printing.

Thereafter, the timer counter 52 generates an interrupt signal at the timing when the usable area of the paper reaches the print head 22B. At this time, the CPU 42 permits black printing, and the head controller 48B outputs the output enable signal OE. As a result, the print head 2
2B is driven according to the contents of the shift registers SR1 and SR2, and performs printing for one line. After that, the head controller 48B reads the dot data for the next one line from the print buffer 45, stores it in the shift registers SR1 and SR2 together with the dot data "0" as described above, and further feeds the paper for one line. The operation of driving the print head 22B is repeated by outputting the output enable signal OE at the above timing.

Further, the CPU 42 commands the operation of the head controller 48C in response to an interrupt signal generated when the paper use area reaches the print head 22B.
The head controller 48C reads the cyan dot data for one line from the print buffer 45, and outputs the dot data DATA for this one line to the dot data DATA.
Divide into 1 and DATA2, and the required number of dot data
0 "is added to these dot data DATA1 and DATA2, and output to the print head 22C together with the number of shift clocks SCK stored in the counter 47C.

Thus, the dot data DATA1 and D
ATA2 is stored in the shift registers SR1 and SR2 of the print head 22C together with the required number of dot data "0". After that, the timer counter 52 generates an interrupt signal at the timing when the usable area of the paper reaches the print head 22C. At this time, the CPU 42 permits cyan printing, and the head controller 48C outputs the output enable signal OE. As a result, the print head 22C is driven according to the contents of the shift registers SR1 and SR2,
Print one line. After that, the head controller 48C reads the dot data for the next one line from the print buffer 45, and as described above, the shift register SR.
1 and SR2 are stored together with the required number of dot data "0", and the output enable signal OE is output at the timing when the paper is fed by one line, thereby repeating the operation of driving the print head 22C.

Further, the CPU 42 commands the operation of the head controller 48M in response to an interrupt signal generated when the utilization area of the paper reaches the print head 22C. The head controller 48M reads out magenta dot data for one line from the print buffer 45, divides the dot data DATA for one line into dot data DATA1 and DATA2, and outputs a required number of dot data "0" to these dot data DATA1. And DATA2 and the number of shift clocks S stored in the counter 47M.
Output to the print head 22M together with CK. In this way, the dot data DATA1 and DATA2 are transferred to the print head 22M.
And the necessary number of dot data "0" are stored in the shift registers SR1 and SR2.

After that, the timer counter 52 generates an interrupt signal at the timing when the usable area of the paper reaches the print head 22M. At this time, the CPU 42 permits printing of magenta, and the head controller 48M outputs the output enable signal OE. As a result, the print head 2
The 2M is driven according to the contents of the shift registers SR1 and SR2, and performs printing for one line. After that, the head controller 48M reads the dot data for the next one line from the print buffer 45, and as described above, the required number of dot data "0" is stored in the shift registers SR1 and SR2.
The operation of driving the print head 22M is repeated by outputting the output enable signal OE at the timing when the sheet is stored and further fed by one line.

Further, the CPU 42 commands the operation of the head controller 48Y in response to an interrupt signal generated when the utilization area of the paper reaches the print head 22M. The head controller 48Y reads one line of yellow dot data from the print buffer 45, divides this one line of dot data DATA into dot data DATA1 and DATA2, and outputs a required number of dot data "0" to these dot data DATA1. And added to DATA2,
The number of shift clocks SCK stored in the counter 47Y
It is also output to the print head 22C.

Thus, the dot data DATA1 and D
ATA2 is stored in the shift registers SR1 and SR2 of the print head 22Y together with the required number of dot data "0". Thereafter, the timer counter 52 generates an interrupt signal at the timing when the usable area of the paper reaches the print head 22Y. At this time, the CPU 42 permits yellow printing, and the head controller 48Y outputs the output enable signal OE. As a result, the print head 22Y is driven according to the contents of the shift registers SR1 and SR2, and prints for one line. After that, the head controller 48Y reads the dot data for the next one line from the print buffer 45 and stores it in the shift registers SR1 and SR2 together with the dot data "0" as described above.
Further, by outputting the output enable signal OE at the timing when the paper is fed by one line, the print head 22Y
The operation of driving is repeated. Printing units 21B, 21
C, 21M and 21Y are black as described above,
The cyan, magenta, and yellow color component images are overlaid and printed on the available area of the paper.

The color printer 2 of the first embodiment
0 operates in the test mode in addition to the normal mode. In this test mode, the deviation test pattern is printed by the printing units 21B, 21C, 21M and 21Y, and the deviation of the printing position of the printing units 21Y, 21M and 21C from the printing position of the printing unit 21B is detected by the operator from this deviation test pattern. It is used to change the printing positions of the printing units 21Y, 21M and 21C in accordance with the measurement result input by operating the keyboard 37. ROM of system control unit CT1
32 stores in advance the first and second test print data used in this test mode. The first test print data is data for printing a deviation test pattern in the main scanning direction X, and the second test print data is data for printing a deviation test pattern in the sub scanning direction P.

When a test mode setting command is input from the keyboard 37, the control circuit of the color printer 20 performs the test print processing shown in FIG. In this test print processing, the CPU 31 reads the first test print data stored in the ROM 32, and outputs the dot image data of the four color components corresponding to the first test print data and the print control data of the predetermined print size and the predetermined print format. RA
Pre-processing relating to the deviation test pattern in the main scanning direction (X-axis direction) that is created in M33 is performed in step ST1. Further, the CPU 31 reads the second test print data stored in the ROM 32 and creates dot image data of four color components corresponding to the second test print data and print control data of a predetermined print size and a predetermined print format in the RAM 33. In step ST2, the pre-processing relating to the deviation test pattern in the sub-scanning direction (paper transport direction, P-axis direction) is performed.

At step ST3, the CPU 42 makes the RAM
The dot image data of the four color components for the deviation test pattern in the main scanning direction X created in 33 and supplied to the dual port RAM 41 are read, and the four color components corresponding to these dot image data are controlled by the same control as in the normal mode. Image printing units 21Y, 21M, 21C and 2
A pattern printing process is performed in which the pattern is printed by overlapping with 1B to obtain a deviation test pattern in the main scanning direction X. In step ST4, the CPU 42 reads the dot image data of the four color components for the deviation test pattern in the sub-scanning direction P, which is created in the RAM 33 and is supplied to the dual port RAM 41, and the dot image data is converted into these dot image data by the control similar to the normal mode. A corresponding four-color component image is printed by the printing units 21Y, 21M, 21C, and 21B in an overlapping manner, and a pattern printing process of obtaining a deviation test pattern in the sub-scanning direction P is performed.

Here, the features of the deviation test pattern printed by the above-mentioned test printing process will be schematically described. As shown in FIG. 6, each deviation test pattern includes a plurality of reference scale bars R arranged at a pitch M in one deviation measurement direction corresponding to the main scanning direction X or the sub-scanning direction P.
In the standard scale with B and this deviation measurement direction,
It is composed of a difference scale having a difference scale bar DB arranged at a pitch N slightly different from the pitch M. The reference scale is printed by one reference printing unit 21B of the printing units 21B, 21C, 21M and 21Y arranged so that images can be overlaid and printed, and the differential scale is printed by the printing units 21C, 21 other than the reference printing unit 21B.
Printed by each of M and 21Y.

The pitch M is set to 30 dots, for example,
The pitch N is set to, for example, 29 dots (or 31 dots), which is slightly smaller than the pitch M. If the print positions of these scales are not displaced, the 0th difference scale bar DB is aligned with the 0th reference scale bar RB as shown in FIG. 6, and the 30th difference scale bar D
B is printed so as to be aligned with the 29th reference scale bar RB. If there is a print position shift, this shift can be measured with an accuracy of 1 dot, which is equal to the difference between the dot numbers M and N.

Color printer 2 of the first embodiment
0 indicates the deviation test pattern in the main scanning direction X shown in FIG. 7 and the deviation test pattern in the sub-scanning direction P shown in FIG. 8 corresponding to the first and second test print data stored in the ROM 32. It is configured to print.

The deviation test pattern shown in FIG. 7 has a single rough scale section SC0, two fine scale sections SC1 and SC2, and two auxiliary scale sections SC3.
The rough scale portion SC0 is provided adjacent to the fine scale portion SC1 in the main scanning direction X, and the fine scale portion S0 is provided.
C1 is provided adjacent to the detailed scale portion SC2 in the sub-scanning direction P. The two auxiliary scale parts SC3 are provided adjacent to the detailed scale parts SC1 and SC2 in the sub-scanning direction P, respectively.

The rough scale section SC0 includes four black reference scales arranged in parallel in the sub-scanning direction P at a predetermined distance, and cyan, magenta, and yellow difference scale bars arranged between these reference scales. And the area symbol provided along the outermost black reference scale
E ”,“ F ”,“ G ”and“ H ”. The four black reference scales are black negative reference scale bars RB arranged from left to right at a pitch of 30 dots in the main scanning direction X,
It has a zero reference scale bar RB and a positive reference scale bar RB, respectively.

Area symbols "E", "F", "G" and "
H ″ is the negative reference scale bar RB, the zero reference scale bar RB, and the positive reference scale bar R in the main scanning direction X.
Areas divided by B are shown respectively. If the print positions are not displaced, the cyan, magenta, and yellow differential scale bar DBs are aligned with the zero reference scale bars RB of the four black reference scales. The area of "E" is -3
1 to -60 dot displacement, "F" region represents -1 to -30 dot displacement, "G" region represents +1 to +30 dot displacement, "H" region Represents the positional deviation from +31 to +60 dots. The predetermined distance substantially coincides with the length of the difference scale bar DB described above.

The detailed scale section SC1 includes four black reference scales arranged in parallel in the sub-scanning direction P at a predetermined distance, and a cyan, magenta, and yellow difference scale arranged between these reference scales. , An identification symbol "GH" provided adjacent to the outermost black reference scale, and bar numbers "0", "5", "1 provided adjacent to other outermost black reference scales.
The four black reference scales each have a plurality of reference scale bars RB arranged from left to right at a pitch of 30 dots in the main scanning direction X, and three cyan, magenta, and The yellow difference scale has a plurality of difference scale bars DB arranged from left to right at a pitch of 29 dots in the main scanning direction X.

Reference scale bar R of each black reference scale
Bs are connected by a straight line extending in the main scanning direction X. If the print position is not displaced, the 0th difference scale bar DB of the difference scale of cyan, magenta, and yellow is aligned with the 0th reference scale bar RB of the four black reference scales, and the 30th difference scale is displayed. The scale bar DB is aligned with the 29th reference scale bar RB. Identification symbol "G
H "is the area symbol" G "in the schematic scale SC0.
And “H” represent the detailed scale corresponding to the area. Bar numbers "0", "5", "10". ． ．
Represents the number of the reference scale bar RB of the black reference scale. The predetermined distance substantially coincides with the length of the difference scale bar DB described above.

The detailed scale section SC2 includes four black reference scales arranged in parallel in the sub-scanning direction P at a predetermined distance, and a cyan, magenta, and yellow difference scale arranged between these reference scales. , An identification symbol "EF" provided adjacent to the outermost black reference scale and bar numbers "0", "5", "1 provided adjacent to other outermost black reference scales.
0 ″ ... and the four black reference scales are
A plurality of reference scale bars RB arranged from left to right at a pitch of 30 dots in the main scanning direction X are provided, and three cyan, magenta, and yellow differential scales are provided in the main scanning direction X.
In, each of the plurality of difference scale bars DB is arranged from left to right with a pitch of 31 dots.

Reference scale bar R of each black reference scale
Bs are connected by a straight line extending in the main scanning direction X. If the print position is not displaced, the 0th difference scale bar DB of the difference scale of cyan, magenta, and yellow is aligned with the 0th reference scale bar RB of the four black reference scales, and the 30th difference scale is displayed. The scale bar DB is aligned with the 31st reference scale bar RB. Identification symbol "E
F "is a region symbol" E "in the schematic scale portion SC0.
, And a detailed scale corresponding to the area indicated by “F”. Bar numbers "0", "5", "10". ． ．
Represents the number of the reference scale bar RB of the black reference scale. The predetermined distance substantially coincides with the length of the difference scale bar DB described above.

The auxiliary scale section SC3 is provided for confirming that there is no displacement in the sub-scanning direction P, and four black reference scale bars RB extending in the main scanning direction X and those extending in the main scanning direction X are provided. It has cyan, magenta, and yellow differential scale bar DBs arranged between reference scale bars RB. If there is no displacement in the sub-scanning direction P, these differential scale bars DB are aligned with the reference scale bar RB. By providing the detailed scale portion SC1 and the detailed scale portion SC2 for measuring the positional deviation in the main scanning direction X and the auxiliary scale portion SC3 for confirming the positional deviation in the sub-scanning direction P, the paper having a narrow width is provided. However, a sufficiently large scale can be printed, and the print position can be easily adjusted.

The deviation test pattern shown in FIG. 8 has a single rough scale portion SC0, two fine scale portions SC1 and SC2, and two auxiliary scale portions SC3.
The general scale section SC0 is provided adjacent to the detailed scale section SC1 in the sub-scanning direction P, and the detailed scale section S0 is provided.
C1 is provided adjacent to the detailed scale portion SC2 in the main scanning direction X. The two auxiliary scale parts SC3 are provided adjacent to the detailed scale parts SC1 and SC2 in the main scanning direction X, respectively. Outline scale part SC0
Is four black reference scales arranged in parallel in the main scanning direction X at a predetermined distance, cyan, magenta, and yellow difference scale bars arranged between these reference scales, and the outermost black reference scale. With area symbols "A", "B", "C", and "D" provided along.

The four black reference scales are a black negative reference scale bar RB, a zero reference scale bar RB, and a positive side reference scale bar RB, which are arranged from top to bottom at a pitch of 30 dots in the sub-scanning direction P. Have. Area symbol "
A "," B "," C "and" D "are the negative reference scale bar RB and the zero reference scale bar R in the sub-scanning direction P.
B and the area divided by the positive reference scale bar RB are shown respectively.

If the printing positions are not shifted, the cyan, magenta, and yellow differential scale bars DB are aligned with the zero reference scale bars RB of the four black reference scales. The area "A" represents the positional deviation from -31 to -60 dots, the area "B" represents the positional deviation from -1 to -30 dots, and the area "C" represents the positional deviation from +1 to +30 dots. The area "D" represents the positional deviation from +31 to +60 dots. Predetermined distance is the above-mentioned difference scale bar DB
Almost matches the length of.

The detailed scale section SC1 includes four black reference scales arranged in parallel in the main scanning direction X at a predetermined distance and a difference scale of cyan, magenta and yellow arranged between these reference scales. , The identification code "CD" provided adjacent to the outermost black reference scale and the bar numbers "0", "5", "1 provided adjacent to the other outermost black reference scales.
0 ″ ... and the four black reference scales are
In the sub-scanning direction P, a plurality of reference scale bars RB arranged from the top to the bottom at a pitch of 30 dots are provided, and three cyan, magenta, and yellow difference scales are provided in the sub-scanning direction P.
In, there are a plurality of difference scale bars DB arranged from top to bottom with a pitch of 29 dots.

Reference scale bar R of each black reference scale
Bs are connected by a straight line extending in the sub-scanning direction P. If the print position is not displaced, the 0th difference scale bar DB of the difference scale of cyan, magenta, and yellow is aligned with the 0th reference scale bar RB of the four black reference scales, and the 30th difference scale is displayed. The scale bar DB is aligned with the 29th reference scale bar RB. Identification code "C
D "is the area symbol" C "in the schematic scale SC0.
And a detailed scale corresponding to the area indicated by "D". Bar numbers "0", "5", "10". ． ．
Represents the number of the reference scale bar RB of the black reference scale. The predetermined distance substantially coincides with the length of the difference scale bar DB described above.

The detailed scale section SC2 includes four black reference scales arranged in parallel at a predetermined distance in the main scanning direction X, and cyan, magenta, and yellow difference scales arranged between these reference scales. , The identification symbol "AB" provided adjacent to the outermost black reference scale, and the bar numbers "0", "5", "1 provided adjacent to the other outermost black reference scales.
0 ″ ... and the four black reference scales are
Each of the plurality of reference scale bars RB is arranged from top to bottom at a pitch of 30 dots in the sub-scanning direction P, and three cyan, magenta, and yellow difference scales are arranged from the top at a pitch of 31 dots in the sub-scanning direction P. Each has a plurality of difference scale bar DBs arranged below.

Reference scale bar R of each black reference scale
Bs are connected by a straight line extending in the sub-scanning direction P. If the print position is not displaced, the 0th difference scale bar DB of the difference scale of cyan, magenta, and yellow is aligned with the 0th reference scale bar RB of the four black reference scales, and the 30th difference scale is displayed. The scale bar DB is aligned with the 31st reference scale bar RB. Identification symbol "A
B "is the area symbol" A "in the schematic scale SC0.
And a detailed scale corresponding to the area indicated by "B". Bar numbers "0", "5", "10". ． ．
Represents the number of the reference scale bar RB of the black reference scale. The predetermined distance substantially coincides with the length of the difference scale bar DB described above.

The auxiliary scale portion SC3 is provided to confirm that there is no displacement in the main scanning direction X, and includes four black reference scale bars RB extending in the sub scanning direction P and those extending in the sub scanning direction P. It has cyan, magenta, and yellow differential scale bar DBs arranged between reference scale bars RB. If there is no displacement in the main scanning direction X, these difference scale bars DB are aligned with the reference scale bar RB. By providing the detailed scale portion SC1 and the detailed scale portion SC2 for measuring the positional deviation in the sub-scanning direction P and the auxiliary scale portion SC3 for confirming the positional deviation in the main scanning direction X, the length is short. It is possible to print a sufficiently large scale even on paper, and it becomes easy to adjust the printing position.

In the color printer 20 described above, the operator observes the deviation test patterns shown in FIGS. 7 and 8,
Printing unit 2 for printing position of printing unit 21B
Observe and measure the deviation of the printing positions of 1C, 21B, and 21Y. In the measurement of the positional deviation in the main scanning direction X, the operator uses the schematic scale portion S of the deviation test pattern shown in FIG.
C0 is checked first, and the cyan, magenta, and yellow difference scale bar D is checked at this rough scale section SC0.
The relative positional relationship between B and the black zero reference scale bar RB is roughly confirmed. For example, when the cyan differential scale bar DB is present in the "G" area between the zero reference scale bar RB and the positive reference scale bar RB in the rough scale section SC0, the positional deviation of the printing unit 21C is caused by the main scanning. Do not exceed +30 dots in direction X.

After confirming the cyan differential scale bar DB existing in the "G" area, the operator checks the detailed scale portion SC1 corresponding to the "G" area, and in this detailed scale portion SC1, the cyan differential scale bar SC1 is displayed. Search for the standard scale bar RB that is aligned with the bar DB. For example, when the 11th reference scale bar RB is aligned with the cyan differential scale bar DB, the positional deviation of the printing unit 21C is +11 dots in the main scanning direction X.

The operator responds to this measurement result "
The correction data "G11" is set to correct the positional deviation of the printing unit 21C in the main scanning direction X.
If the cyan differential scale bar DB exists in the "H" area beyond the positive reference scale bar RB, the printing unit 21
The positional deviation of C is +41 dots (3
0 dots + 11 dots). In this case, the operator sets the correction data "H11" corresponding to this measurement result in order to correct the positional deviation of the printing unit 21C in the main scanning direction X.

If the cyan difference scale bar DB is "F" between the zero reference scale bar RB and the negative side reference scale bar RB.
If it is printed in the area, the detailed scale portion SC2 corresponding to the "F" area is checked. Further, the positional deviation of the magenta and yellow printing units 21M and 21C is also measured from the deviation test pattern shown in FIG. 7, similarly to the positional deviation measurement of the cyan printing unit 21C.

On the other hand, in the measurement of the positional deviation in the sub-scanning direction P, the operator first checks the rough scale portion SC0 of the deviation test pattern shown in FIG. 8, and at this rough scale portion SC0, the cyan, magenta and yellow difference scale bars are checked. The relative positional relationship between the DB and the black zero reference scale bar RB is roughly confirmed. For example, the cyan difference scale bar DB is located between the zero reference scale bar RB and the negative reference scale bar RB in the rough scale section SC0.
When it exists in the B "area, the positional deviation of the printing unit 21C does not exceed -30 dots in the sub-scanning direction P.

After confirming the cyan differential scale bar DB existing in the "B" area, the operator checks the detailed scale portion SC2 corresponding to the "B" area, and in the detailed scale portion SC2, the cyan differential scale bar DB is checked. Search for the standard scale bar RB that is in line with DB. For example, when the sixth reference scale bar RB is aligned with the cyan differential scale bar DB, the positional deviation of the printing unit 21C is -6 dots in the sub-scanning direction P. The operator sets correction data "B6" corresponding to this measurement result in order to correct the positional deviation of the printing unit 21C in the sub-scanning direction P.

When the cyan differential scale bar DB exists in the area "A" that exceeds the negative reference scale bar RB, the positional deviation of the printing unit 21C is -3 in the sub-scanning direction P.
It becomes 6 dots [(-30) + (-6) dots]. In this case, the operator corresponds to this measurement result, "A6"
Correction data is set in order to correct the positional deviation of the printing unit 21C in the sub-scanning direction P.

If the cyan differential scale bar DB is "C" between the zero reference scale bar RB and the positive reference scale bar RB.
If it is printed in the area, the detailed scale portion SC1 corresponding to the "C" area is checked. Further, the positional deviation of the magenta and yellow printing units 21M and 21C is also measured from the deviation test pattern shown in FIG. 8 similarly to the positional deviation measurement of the cyan printing unit 21C. FIG. 9 is a diagram showing a correction data setting process performed by the control circuit of the color printer 20. This correction data setting process is performed in the test mode after printing the deviation test pattern in the main scanning direction X and the sub scanning direction P shown in FIGS. The operator inputs the correction data corresponding to the measurement result of the positional deviation of the printing units 21Y, 21M, 21C via the keyboard 37 or the host computer. The correction data in the main scanning direction X is confirmed in step ST11, and the nonvolatile RAM
It is stored in step 51 in step ST12. On the other hand, the correction data in the main scanning direction P is confirmed in step ST13 and stored in the nonvolatile RAM 51 in step ST14. In step ST15, the correction data is set in the printing unit 2
It is checked whether it is completed for 1Y, 21M and 21C. The correction data processing ends after repeatedly executing the above steps.

FIG. 10 shows a correction process performed by the control circuit of the color printer 20. This correction process is performed after the correction data setting process shown in FIG. 9 or when the power is turned on.
When the correction data in the main scanning direction X is read from the nonvolatile RAM 51 in step ST21, the shift clock SCK
Is obtained based on the read correction data in step ST22, and is preset in the corresponding counter of the head controller 47 as the print control data of the corresponding print unit in step ST23. For example, when the correction data is "G11", the print control data is set to the shift clock number that shifts the print position of the corresponding print unit by -11 dots in the main scanning direction X.

In step ST24, it is checked whether all the correction data in the main scanning direction X have been read. If the correction data in the main scanning direction X remains without being read,
Step ST21 is executed again. Step ST24
When it is detected that all the correction data in the main scanning direction X have been read out in step ST, the correction data in the sub scanning direction P is determined in step ST.
At 25, it is read from the nonvolatile RAM 51.

Then, the number of paper carrying steps is S
It is determined based on the read correction data at T26, and is further preset in the timer counter 52 as print control data of the corresponding print unit at step ST27. For example, if the correction data is "B6", the print control data is set to the number of paper transport steps that shifts the print position of the corresponding print unit by +6 dots in the sub-scanning direction P. In step ST28, it is checked whether all the correction data in the main scanning direction X have been read. If the correction data in the main scanning direction X remains without being read, step ST25 is executed again.

Hereinafter, the print heads 22Y, 22M, 22C
And head controller 48 for controlling 22B respectively
The operation of Y, 48M, 48C and 48B will be described in more detail. These head controllers 48Y, 48M, 4
In 8C and 48B, counters 47Y, 47M, 4
7C and 47B hold print control data representing the shift clock number of 680 in the initial state, respectively.

Here, the operation of the head controller 48C will be described, and the head controllers 48Y, 48M and 48B which are configured similarly to the head controller 48C will be described.
The description of the operation of is omitted. In the correction process shown in FIG. 10, the print control data in the counters 47Y, 47M and 47C are updated to correct the positional deviation of the print units 21Y, 21M and 21C in the main scanning direction X, respectively.
The print control data in the counter 47B is not updated.

FIG. 11 is a diagram showing an operation performed by the head controller 48C when the positional deviation does not exist in the main scanning direction. In this case, the head controller 48C sequentially supplies 680 shift clocks SCK to the shift registers SR1 and SR2 forming the line buffer shown in FIG. 4 in the print head 22C in accordance with the print control data held in the counter 47C, and at the same time shifts these shifts. 680 dot data are supplied to the shift registers SR1 and SR2 in synchronization with the clock SCK.

As shown in FIG. 11, the shift register SR
1 sequentially receives 640-bit dot data DATA1 and the subsequent 40-bit dot data "00 ... 0", and the shift register SR2 receives 80-bit dot data "00 ... 0". The subsequent 600 bits of dot data DATA2 are sequentially received. The dot data DATA1 corresponds to the dot data D640 to D1 of the dot data for one line read from the print buffer 45 to the head controller 48C. The dot data DATA2 is the dot data D1200 to D601 of the dot data for one line read from the print buffer 45 to the head controller 48C.
Corresponding to.

Shift clock SCK (C1 to C40)
The dot data D640 to D601 assigned to the shift register SR1 are deleted due to overflow of the shift register SR1, and the dot data "00 ... 0" assigned to the shift clock SCK (C1 to C40) are deleted due to overflow of the shift register SR2. . As a result, the dot data “00 ... 0” is stored in the line buffer bits R1 to R40, and the dot data D1 to D1200 is stored in the line buffer bits R41 to R1.
240, and the dot data “00 ... 0” is stored in bits R1241 to R1280 of the line buffer.

FIG. 12 is a diagram showing an operation performed by the head controller 48C when the positional deviation in the main scanning direction X is corrected by the increase in the number of shift clocks SCK. When the print control data held in the counter 47C is updated to "680 + n" (n is a positive integer of 40 or less), the head controller 48C causes the counter 47C to
680 + n shift clocks SCK are sequentially supplied to the shift registers SR1 and SR2 in the print head 22C in accordance with the print control data held in C, and 680 + n dot data are shifted to the shift registers SR1 and SR2 in synchronization with these shift clocks SCK. Supply to each.

As shown in FIG. 12, the shift register SR
1 is 640-bit dot data DATA1 and 40 + n-bit dot data "00 ... 0" following this.
Sequentially, the shift register SR2 receives 80-bit dot data "00 ... 0" and the following 600-
The dot data DATA2 for n bits are sequentially received.
The dot data DATA1 corresponds to the dot data D640 to D1 of the dot data for one line read from the print buffer 45 to the head controller 48C. Also, the dot data DATA2 is stored in the print buffer 4
5 corresponds to the dot data D1200 to D (601-n) of the dot data for one line read to the head controller 48C.

The shift clocks SCK (C1 to C (40
+ N)) assigned to dot data D640 to D640
(601-n) is deleted due to the overflow of the shift register SR1, and the dot data "0" assigned to the shift clock SCK (C1 to C (40 + n))
0. ． ． 0 "is deleted by overflow of the shift register SR2. As a result, the dot data" 0 "is deleted.
0. ． ． 0 "is the bits R1 to R (4 of the line buffer
0 + n), and the dot data D1 to D1200
From the line buffer bits R (41 + n) to R (12
40 + n), and the dot data is “00 ... 0”.
Are bits R (1241 + n) to R1 of the line buffer
280.

FIG. 13 is a diagram showing an operation performed by the head controller 48C when the positional deviation in the main scanning direction X is corrected by the decrease in the number of shift clocks SCK. When the print control data held in the counter 47C is updated to "680-m" (m is a positive integer of 40 or less), the head controller 48C determines the counter 47C.
680-m shift clocks SCK are sequentially supplied to the shift registers SR1 and SR2 in the print head 22C in accordance with the print control data held in the shift heads, and 680-m dot data are shifted in the shift registers in synchronization with the shift clocks SCK. Supply to SR1 and SR2 respectively.

As shown in FIG. 13, the shift register SR
1 is 640-bit dot data DATA1 and 40-m-bit dot data "00 ... 0" following this.
Sequentially, the shift register SR2 receives 80 bits of dot data "00 ... 0" followed by 600+
The dot data DATA2 for m bits are sequentially received.
The dot data DATA1 corresponds to the dot data D640 to D1 of the dot data for one line read from the print buffer 45 to the head controller 48C. Further, the dot data DATA2 is stored in the print buffer 45.
From the dot data D1200 to D of the dot data for one line read from the head controller 48C
Corresponds to (601 + m).

Shift clock SCK (C1 to C (40
-M)) to the dot data D640 to D640
(601 + m) is deleted due to overflow of the shift register SR1, and shift clock SCK (C1 to C
(40-m)) assigned to dot data “0
0. ． ． 0 "is deleted by overflow of the shift register SR2. As a result, dot data" 0 "
0. ． ． 0 "is the bits R1 to R (4 of the line buffer
0-m), and the dot data D1 to D1200
From the line buffer bits R (41-m) to R (12
40-m), and the dot data is "00 ... 0".
Is from line buffer bits R (1241-m) to R1
280.

The positional deviation in the sub-scanning direction P is corrected by controlling the print timing of the print units 21Y, 21M, 21C and 21B. Print head 22
B, 22C, 22M and 22Y start to be driven when the available area of the paper reaches the print heads 22B, 22C, 22M and 22Y, respectively. The timer counter 52 detects the print heads 22B and 22B from the position sensor 29.
The first to fourth number of sheet carrying steps determined corresponding to the distances to C, 22M and 22Y are held as print control data.

In this color printer 20, the position sensor 29 and the print heads 22B, 22C, 22M and 22Y are set apart from each other by a distance corresponding to 1000 dots, and five driving pulses are arranged in the sub-scanning direction P. The feed motor unit 4 is used to convey one dot of paper.
8 pulse motors. In this case, the timer counter 52 has 5000 steps, 10000 steps,
The 1st to 4th print control data representing the 1st to 4th sheet conveying step numbers of 15000 steps and 20000 steps, respectively, are held in the initial state.

When the positional deviation does not exist in the sub-scanning direction P, the CPU 42 operates the timer counter 52 in response to the interrupt signal from the position sensor 29, and 5000.
The head controller 48 starts the drive of the print head 22B in response to an interrupt signal generated from the timer counter 52 every time the number of paper conveyance steps is counted.
B instructing the head controller 48C to start driving the print head 22C in response to an interrupt signal generated from the timer counter 52 when the number of sheet conveying steps of 10000 steps is counted, and the sheet conveying step of 15000 steps is performed. When the number is counted, the head controller 48M is instructed to start driving the print head 22M in response to an interrupt signal generated from the timer counter 52, and when the number of sheet conveyance steps of 20000 steps is counted, the timer counter 52 In response to the generated interrupt signal, the head controller 48Y is instructed to start driving the print head 22Y. In the correction process shown in FIG. 10, the second, third, and fourth print control data are printed by the printing unit 2 with respect to the printing unit 21B in the sub-scanning direction P.
It is updated to correct the positional deviations of 1C, 21M, and 21Y, respectively.

Here, the drive start timing of the print head 22C will be described, and the description of the drive start timing of the print heads 22Y, 22M, and 22B configured similarly to the print head 22C will be omitted. When the positional deviation of the print head 22C is, for example, −6 dots in the sub-scanning direction P, the number of paper conveyance steps in the timer counter 52 is 10000+ (6 × 5) in order to correct this positional deviation.
= 10030 steps are updated.

The CPU 42 responds to the interrupt signal generated from the timer counter 52 when the number of paper conveyance steps of 10030 is counted, in response to the print head 2.
The head controller 48C is instructed to start driving 2C.
As a result, the print position of the print head 22C is shifted by +6 dots in the sub-scanning direction P so as to be separated from the print head 22B. If this misalignment is +6 dots, the number of paper conveyance steps is 10,000- (6 × 5).
= 9070 steps are updated.

The CPU 42 responds to the interrupt signal generated from the timer counter 52 when the number of paper conveyance steps of 9070 steps is counted, and the print head 2
The head controller 48C is instructed to start driving 2C.
As a result, the print position of the print head 22C is shifted so as to approach the print head 22B by -6 dots in the sub-scanning direction P. When the deviation test patterns in the main scanning direction X and the sub-scanning direction P described above are printed again after the correction processing shown in FIG. 10, it can be confirmed that the positional deviation has actually been eliminated as shown in FIGS. 14 and 15.

Color printer 2 of the first embodiment
0 is a ROM for the first and second test print data that defines the deviation test pattern in the main scanning direction X and the sub scanning direction P.
32, the deviation test pattern in the main scanning direction X and the sub scanning direction P is actually printed in the test mode.
Each deviation test pattern is printed by the printing unit 21B, and in the corresponding deviation measurement direction, a reference scale having a plurality of reference scale bars arranged at the first pitch and the printing units 21C, 21M, and 21Y are arranged adjacent to the reference scale in parallel. And a difference scale having difference scale bars arranged at a second pitch different from the first pitch by one dot in the corresponding deviation measurement direction.

The operator searches for a reference scale bar that is in line with the difference scale bar in each deviation test pattern,
The printing units 21C, 21 with respect to the printing unit 21B in the corresponding deviation measurement direction from the order of the reference scale bar
Measure the deviation of the printing positions of M and 21Y. The displacement is
Since each deviation test pattern is represented by the relative positional relationship between the reference scale bar and the difference scale bar, measurement can be performed easily and with high accuracy. Further, since the operator can measure the positional deviation without using a microscope, it is possible to reduce the burden on the operator, the measurement time, and the variation in the measured value depending on the operator. Further, the color printer 20 can correct the positional deviation based on the correction data input from the keyboard 37. Incidentally, when the difference between the pitch of the reference scale bar and the pitch of the differential scale bar is 1 dot, this measurement accuracy is improved to 1 dot.

In the first embodiment, the deviation test pattern in the sub-scanning direction P has the rough scale portion SC0 and the fine scale portions SC1 and SC2. These detailed scale parts SC1 and SC2 are, for example, the print heads 22Y, 2 for the heating element line of the print head 22B.
It can be used to measure the deviation of the inclination of the heating element lines of 2M, 22C and 22B. In this case, for example, as shown in FIG. 16, a control for arranging the pair of detailed scale portions SC2 (or the pair of detailed scale portions SC1) on the sheet as close as possible to both ends of the sheet in the main scanning direction X is performed. Done. The deviation of the inclination is measured as a difference in the order of the reference scale bars by searching the differential scale bar and the reference scale bar that are aligned with each other in the pair of detailed scale portions SC2. This deviation can be corrected by changing the arrangement of the dots forming this pattern, for example, when creating a dot image pattern in the RAM 33.

A color printer according to the second embodiment of the present invention will be described below with reference to FIGS. 17 to 21. This color printer is configured in the same manner as the color printer of the previous embodiment, except for the following, in order to automatically measure the positional deviation from the deviation test pattern in the main scanning direction X and the sub scanning direction P. Therefore, the same parts as those in the previous embodiment are designated by the same reference numerals, and the detailed description of these parts will be omitted. FIG. 17 shows the color printer 61.
19 is a diagram schematically showing the internal structure of FIG. 18, and FIG. 18 is a diagram showing a control circuit of the color printer 61.

As shown in FIG. 17, the color printer 61 includes a CCD (charge coupled device) image sensor 62.
Further has. The CCD image sensor 62 is disposed adjacent to the exit of the paper transport path that discharges the paper processed by the printing units 21B, 21C, 21M, and 21Y in the test mode, and the deviation in the main scanning direction X and the sub scanning direction P is detected. Read the color image of the test pattern. This color image is output from the image sensor 62 to the input / output port 34.
Are stored in the RAM 33. CPU3
The control programs 1 and 42 correspond to the printing units 21C, 21M and 21 corresponding to the printing positions of the printing unit 21B.
It is changed so that the deviation of the printing position of Y can be automatically measured. In the test mode, the control circuit of the color printer 61 controls the step ST3 as shown in FIG.
A test print process is performed with 0, and then step ST31
Perform correction processing with.

FIG. 20 is a diagram showing the test printing process shown in FIG. 19 in more detail. In this test print process, C
The PU 31 reads the first test print data stored in the ROM 32 and creates dot image data of four color components corresponding to the first test print data and print control data of a predetermined print size and a predetermined print format in the RAM 33. Pre-processing relating to the deviation test pattern in the main scanning direction X is performed in step ST35. Furthermore, C
The PU 31 reads the second test print data stored in the ROM 32 and creates dot image data of four color components corresponding to the second test print data and print control data of a predetermined print size and a predetermined print format in the RAM 33. Pre-processing relating to the deviation test pattern in the sub-scanning direction P is performed in step ST36.

At step ST37, the CPU 42 causes the R
The dot image data of the four color components stored for the deviation test pattern in the main scanning direction X, which is created in the AM33 and is supplied to the dual port RAM 41, is read out, and the dot image data corresponding to these dot image data is controlled by the same control as in the normal mode. 4 color component image printing unit 21Y, 21
M, 21C and 21B are overlaid and printed, thereby performing a pattern printing process of obtaining a deviation test pattern in the main scanning direction X. In step ST38, the CPU 42
Is created in RAM33, and dual port RAM4
The dot image data of the four color components stored for the deviation test pattern in the sub-scanning direction P supplied to the No. 1 is read,
By the same control as the normal mode, the four color component images corresponding to these dot image data are printed by the printing unit 21Y,
21M, 21C, and 21B are overlapped and printed to obtain a deviation test pattern in the sub-scanning direction P, thereby performing a pattern printing process.

FIG. 21 shows the correction process shown in FIG. 20 in more detail. In this correction process, the CPU 31 executes step S
At T41, the CCD image sensor 62 sequentially reads the images of the deviation test patterns in the main scanning direction X and the sub scanning direction P. In step ST42, the CPU 31 analyzes the image of the deviation test pattern in the main scanning direction X, and in step ST
At 43, the positional deviation of the printing units 21Y, 21M and 21C with respect to the printing unit 21B in the main scanning direction X is measured from the analysis result of the image of the deviation test pattern,
In step ST44, the correction data corresponding to this displacement is stored in the non-volatile RAM 51.

Further, in step ST45, the CPU 31 analyzes the image of the deviation test pattern in the sub-scanning direction P, and in step ST46, from the analysis result of the image of the deviation test pattern, the printing units 21Y and 21M for the printing unit 21B in the sub-scanning direction P are analyzed. And 21C are measured, and the correction data corresponding to this positional deviation are stored in the non-volatile RAM 51 in step ST47. The control circuit performs the correction process shown in FIG. 10 subsequent to the correction process shown in FIG. As a result, the initial print control data stored in the timer counter 52 and the counters 47Y, 47M, and 47C is updated based on the correction data stored in the nonvolatile RAM 51.

The color printer 6 according to the second embodiment
1 has the same advantages as the color printer 20 of the first embodiment described above, and can eliminate the need for the operator to measure the positional deviation. Therefore, the burden on the operator and the time required to correct the positional deviation can be further reduced. In each of the above embodiments, the printing unit 2
1Y, 21M, 21C and 21B were configured to print using the ink ribbon and thermal printhead. However, the present invention is not limited to this, and the printing units 21Y, 21M, 21C, and 21B may be configured to perform printing by using, for example, an inkjet type print head, and further, a photoconductor to be electrophotographic processed. The printing may be performed using a drum.

[0097]

As described above in detail, according to the present invention,
It is possible to provide a printing device capable of printing a deviation test pattern capable of easily and highly accurately measuring the deviation between the printing positions of a plurality of images superimposed on a sheet. Further, it is possible to provide a printing apparatus that can automatically eliminate the deviation between the printing positions of a plurality of images that are overlapped on a sheet by using this deviation test pattern. Further, it is possible to provide a deviation test pattern capable of easily and highly accurately measuring the deviation between the printing positions of a plurality of images superimposed on a sheet.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an internal structure of a color printer according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a control circuit of the color printer of the embodiment.

FIG. 3 is a block diagram showing a relationship between a head control unit and a head unit of the color printer according to the embodiment.

FIG. 4 is a diagram showing a line buffer including two shift registers provided in each thermal print head of the color printer of the embodiment.

FIG. 5 is a flowchart showing a test print process performed by the control circuit of the color printer of the same embodiment.

FIG. 6 is a diagram for explaining characteristics of a deviation test pattern printed by a test printing process performed by the color printer of the embodiment.

FIG. 7 is a diagram showing a deviation test pattern printed for measuring a positional deviation in the main scanning direction by a test printing process performed by the color printer of the embodiment.

FIG. 8 is a diagram showing a deviation test pattern printed for measuring a positional deviation in the sub-main scanning direction by a test printing process performed by the color printer of the embodiment.

FIG. 9 is a flowchart showing a correction data setting process performed by the control circuit of the color printer of the same embodiment.

FIG. 10 is a flowchart showing a correction process performed by the control circuit of the color printer according to the same embodiment.

FIG. 11 is a time chart showing an operation performed by the head controller when there is no positional deviation in the main scanning direction in the color printer of the same embodiment.

FIG. 12 is a time chart showing an operation performed by the head controller when the positional deviation in the main scanning direction in the color printer of the embodiment is corrected by the increase in the number of shift clocks.

FIG. 13 is a time chart showing an operation performed by the head controller when the positional deviation in the main scanning direction in the color printer of the embodiment is corrected by the reduction of the shift clock number.

FIG. 14 is a diagram showing a deviation test pattern printed for measuring the positional deviation in the main scanning direction after the correction processing in the color printer of the embodiment.

FIG. 15 is a diagram showing a deviation test pattern printed for measuring the positional deviation in the sub-scanning direction after the correction processing of the color printer of the embodiment.

FIG. 16 is a diagram showing a deviation test pattern capable of confirming that the thermal print head of the color printer of the embodiment is parallel to the main scanning direction.

FIG. 17 is a diagram schematically showing an internal structure of a color printer according to a second embodiment of the invention.

FIG. 18 is a block diagram showing a control circuit of the color printer of the embodiment.

FIG. 19 is a flowchart for explaining the operation of the control circuit of the color printer according to the same embodiment.

FIG. 20 is a flowchart showing a test printing process performed by the color printer of the embodiment.

FIG. 21 is a flowchart showing correction processing performed by the color printer according to the same embodiment.

FIG. 22 is a diagram showing a first deviation test pattern printed for measuring the positional deviation in the main scanning direction in the conventional color printer.

FIG. 23 is a diagram showing a second deviation test pattern printed for measuring the positional deviation in the sub-scanning direction in the conventional color printer.

[Explanation of symbols]

22Y, 22M, 22C, 22B ... Thermal print head, 31, 42 ... CPU, 32 ... ROM, 41 ... Dual port RAM, 48Y, 48M, 48C, 48B ... Head controller, SC0 ... Outline scale section, SC1, SC2 ... Details Scale part, SC3 ... Auxiliary scale part.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-4-153053 (JP, A) JP-A-61-31276 (JP, A) JP-A-2-60785 (JP, A) JP-A-3- 246060 (JP, A) JP-A-7-81190 (JP, A) JP-A-2-125256 (JP, A) JP-A-4-338625 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/325 B41J 5/30 B41J 35/16 H04N 1/40 H04N 1/46

Claims (3)

(57) [Claims] 1. A plurality of printable images arranged so as to overlap each other.
Print units and control these print units to print images overlaid
And a print control circuit for controlling the print control circuit in the test mode.
Controls one standard printing unit of knit and measures one deviation
A plurality of scale bars arranged at a pitch M in a fixed direction
Print the standard scale you have,
Control the outside printing unit to move in the 1 deviation measurement direction.
Scales arranged at a pitch N slightly different from the pitch M
A difference scale with a bar next to the reference scale
Print in parallel, and use the reference scale and difference scale
From the deviation test pattern consisting of
The print position of the 1 standard print unit should be
Measure the deviation of the printing position of the other printing unit and
Change the printing position of the other printing unit according to the above measurement results.
A further test control circuit and the reference printing unit are controlled to print a reference scale having a plurality of scale bars arranged at a pitch M in another deviation measuring direction different from the one deviation measuring direction, and other than the reference printing unit. The printing unit is controlled to print a difference scale having scale bars arranged at a pitch N slightly different from the pitch M in the other deviation measurement direction in parallel adjacent to the reference scale. A deviation of the printing position of the other printing unit with respect to the printing position of the reference printing unit is measured in the other deviation measuring direction from a second deviation test pattern composed of a scale, and the printing position of the other printing unit is measured. A printing apparatus having a second test control circuit for changing the value according to the measurement result. 2. A reference scale having a plurality of scale bars, which are printed by one reference printing unit of a plurality of printing units arranged so as to print images in an overlapping manner and are arranged at a pitch M in one deviation measurement direction, A difference scale having scale bars that are printed in parallel adjacent to the one reference scale by a printing unit other than the one reference printing unit and are arranged at a pitch N slightly different from the pitch M in the one deviation measurement direction; A first detailed scale portion configured by the reference scale and the difference scale with a predetermined length shorter than the pitch M, and a plurality of scales printed by the reference printing unit and arranged at the pitch M in the one deviation measurement direction. The standard scale with a bar and printing units other than the standard printing unit described above A second detailed scale portion which is printed in parallel adjacent to the quasi-scale and has a graduated scale having scale bars arranged at a pitch L longer than the pitch M by the predetermined length in the one deviation measurement direction. Deviation test pattern characterized by. 3. A reference scale having a plurality of scale bars printed by the one reference printing unit and arranged at the pitch M in the one deviation measurement direction, and adjacent to the reference scale by a printing unit other than the one reference printing unit. 3. The deviation test pattern according to claim 2 , further comprising: a scale bar that is printed in parallel and that is located at the center of the reference scale and a schematic scale portion that is composed of scale bars that are aligned in a straight line.