JP2847916B2 - Printing position correction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a dot impact type or an ink jet type in which a carriage is moved in both left and right directions of a sheet facing a platen and printed on the sheet along both directions. A serial printer, wherein the printing speed for printing in both the left and right directions (forward printing direction and reverse printing direction) of the paper is at least 2
The present invention relates to a method of correcting a printing position in a printing device that can be changed to more than a type.

[Conventional technology]

In recent printing apparatuses, in order to speed up the printing operation, a printing operation for one line is performed from left to right (forward printing direction) of the paper, and then the paper is vertically fed by one line, and then the right side of the paper is printed. , A bidirectional printing operation is performed, such as performing a printing operation for the next one line from left to the left (reverse printing direction).

By the way, as a mechanism for moving the carriage left and right in the printing apparatus, a timing belt attached to the carriage is moved left and right from a DC servo motor via a transmission gear group. Due to the play (backlash) between a pair of gears that mesh with each other,
A printing position shift occurs in which the printing position in the forward printing direction and the printing position in the reverse printing direction are shifted left and right.

In addition, when the printing speed is changed, the time delay from the printing command by the control device in the printing apparatus to the actual operation of the printing unit (for example, the protruding movement of the dot pin) (electrical time delay +
There is a flying time, and this time delay is fixed by the design of the apparatus. Therefore, if the moving speed (printing speed) of the carriage becomes faster, the print position deviation amount in the bidirectional printing increases.

Accordingly, as a method of correcting a printing position in a printing apparatus having a bidirectional printing function of this type, for example, Japanese Patent Application Laid-Open No. 63-15775 discloses a printing position in a forward printing direction of a carriage at each printing speed. A left-right error with respect to the printing position in the printing direction, that is, a movement error of the carriage is detected, and each movement error corresponding to the plurality of printing speeds is stored in a memory in advance, and any printing of the plurality of printing speeds is performed. When performing two-way printing by selecting the speed, the printing timing when performing reverse printing is corrected by reading the detected movement error from the memory based on the printing position in the forward printing direction at that printing speed. Had adopted the method.

[Problems to be solved by the invention]

However, as in the above-described prior art, the problem that the printing start position itself shifts when the printing speed is different cannot be eliminated by simply correcting only the displacement of the bidirectional printing for each moving speed. there were.

For example, when printing on a single sheet of paper, if the printing operation involves a mixture of character lines and ruled line lines, to improve printing efficiency, set the printing speed of the character printing line to be slow and set If the printing speed (carriage movement speed) differs for each line of paper, such as setting the printing speed faster in a line, a printing position shift occurs between the lines.

An object of the present invention is to solve this problem and to provide a correction method that does not shift the printing position at any printing speed and between any printing lines.

[Means for solving the problem]

In order to achieve the above object, an invention according to a first aspect of the present invention is to move a carriage on which a print head disposed opposite to a platen is mounted at the same speed in a forward printing direction and a reverse printing line direction. And the moving speed can be changed to at least two or more types, wherein the printing position in one of the forward printing direction and the reverse printing direction at the moving speed of each type is set as a reference. After correcting the misregistration amount of the printing position in the other printing direction, the misalignment amount between the reference printing positions between the different kinds of moving speeds is determined based on the reference printing position at one moving speed. In the invention according to the second aspect, on the contrary, the forward printing direction or the reverse printing at one of the plurality of types of moving speeds is performed. After correcting the printing position deviation amount of the printing position in one of the forward printing direction or the reverse printing direction at another moving speed based on the printing position in one of the printing directions, The correction of the print position shift amount in the other direction with respect to the print position in one of the forward print direction and the reverse print direction at each moving speed is executed.

〔Example〕

Next, an embodiment applied to a dot-type serial printer as an impact printer will be described. In FIGS. 1 and 2, reference numeral 1 denotes a fixed elongated platen body in a printing apparatus, and 2 denotes a platen body 1. The print head 2 and a replaceable ribbon cassette 3 containing an ink ribbon are mounted on a carriage 4 by a print head which is disposed so as to move along the surface and along the longitudinal direction thereof. The carriage 4 is fitted on the support shaft 5 via the boss 4a so as to be movable along the axis of the support shaft 5 arranged in parallel along the longitudinal direction of the platen body 1. Provide movably. This boss 4a is
Is slidable in the axial direction, but the shape is determined so that it cannot slide in the rotation direction about the axis. The axis of the support shaft 5 is decentered by an appropriate amount (e) with respect to the axis of the boss 4a.

In this embodiment, the print head 2 is arranged to face the platen body 1 in a horizontal direction.

The carriage 4 is carried at an appropriate position of the timing belt 6 as an endless belt, and one of the plurality of pulleys 7a, 7b, 7c, 7d around which the timing belt 6 is wound has a drive pulley 7a. The carriage 4 which is driven via a speed change gear associated with a DC servo motor 8 which can rotate in the reverse direction and which is attached to the timing belt 6 in accordance with the forward / reverse drive of the DC servo motor 8 moves in the longitudinal direction of the platen body 1 (of the paper 15). (The width direction).

The driving force from the step motor 9 is transmitted to the sector gear 12 attached to one end of the support shaft 5 through the transmission gears 10 and 11, and the carriage 4 is driven in accordance with the rotation angle of the support shaft 5. The gap (print gap) between the print head 2 and the platen body 1 mounted on the printer is adjusted to be wide or narrow.

Reference numeral 13 denotes an auxiliary shaft disposed in parallel with the support shaft 5, and a restricting piece 14 slidably and loosely fitted to the auxiliary shaft 13 protrudes from the carriage 4 to maintain the posture of the carriage 4. I have.

The paper 15 is transferred to the platen 1 by a transporting means (not shown).
And the ink ribbon in the ribbon cassette 3 is interposed between the paper 15 and the print head 2 so as to be appropriately moved substantially parallel to the moving direction of the carriage 14. A cassette is provided at a fixed position, and the ink ribbon is moved to the carriage 4 (print head 2).
May be configured to move relative to.

FIG. 3 is a block diagram of a microcomputer as a control device of the present invention, and reference numeral 16 denotes a central processing unit (CP).
U) and 17 are interfaces for transmitting and receiving data to and from the host computer, and 18 is a character pattern of a commonly used kanji such as a first-level kanji and a second-level kanji and a character code for designating the pattern in advance. A read-only character generator (character generator), 19 is a read-only non-kanji character generator that stores in advance non-kanji characters such as alphabets, numbers, hiragana characters, and katakana characters, and 20 prints This is a work memory in which a control signal for controlling the operation of the mechanism of the apparatus can be read and written.

Reference numeral 21 is a memory for registering an external character for storing the character pattern of the external character sent from the host computer in accordance with the external character registration command and the corresponding character code, and reference numeral 22 is additionally installed at the request of the user. The optional memory that can be read and written
M), the memories 21 and 22 are preferably electrically erasable / writable non-volatile memories (EEPROMs) or memories capable of retaining stored contents even when the main power is turned off by a backup power supply.

Reference numeral 23 denotes a print for calling a predetermined character from the character generators 18 and 19 and memories 21 and 22 for external characters, and converting the character to vertical writing or horizontal writing in accordance with a command from the central processing unit 17. Data processing IC (gate array),
24 is a non-volatile memory (EEPROM) that can write data for fine adjustment according to the mechanism of the printing unit, code
Reference numeral 25 denotes a dip switch for switching the mode of the interface 17 or switching the font of the character.

Reference numeral 26 denotes an IC (gate array) that controls a print data memory (print buffers 27 and 28), including a duty counter for regulating the timing of printing and the like. Two-line print buffer 27,2 for temporarily storing data of minutes
8 is for printing one line based on the data accumulated in one print buffer 27 while the other print buffer
By accumulating the character data of the next line at 28, the bidirectional printing operation can be performed quickly.

Reference numeral 29 denotes an IC (gate array) for controlling the serial dot print head drive circuit 30, which instructs the print head 2 to project dot pin protrusion data to the print head drive circuit 30.

Reference numeral 31 denotes a switch panel as an operation unit of the printing apparatus.The switch panel 31 switches between an online state in which data can be exchanged between the host computer and the printing apparatus and an offline state in which data cannot be exchanged, A switch for instructing "line feed" or "page break" when offline is provided.

Reference numeral 32 denotes a limit switch for stopping printing operation and paper feeding by sensing that the paper has run out, reference numeral 33 denotes an alarm drive circuit for warning by a buzzer or the like when detecting paper feeding or paper absence, and reference numeral 34 cools the inside of the printing apparatus. A fan driving circuit for driving the fan for the power supply switch, which is related to on / off of the power switch.

Reference numeral 35 denotes a motor drive circuit for driving a DC servo motor 8 for moving the carriage 4 in the forward printing direction and reverse printing direction, 36 denotes an encoder for counting the number of rotations of the DC servo motor 8, and 37 denotes a sheet 15 Vertical (line feed)
A paper feed motor driving circuit 38 for driving a stepping motor is provided, and an automatic cut sheet feeder 38 is provided for automatically feeding cut sheets.

Reference numeral 39 denotes a speed changeover switch for switching the printing speed between at least two types. For example, the printing speed can be switched between a standard speed (110 characters / second) and a double speed (220 characters / second). It has become.

Note that this printing speed switching can also be performed by a command from the host computer.

Reference numeral 40 denotes a gap adjusting drive circuit for adjusting the printing gap by driving the stepping motor 9 to rotate forward and backward. As shown in FIG. 2, the sector gear 12 is rotated in the direction of arrow A as shown in FIG. For example, the support shaft 5 that rotates integrally with the sector gear 12
Is eccentric with respect to the boss 4a by the dimension (e),
The printing gap becomes large, and if it turns in the direction of arrow B,
The printing gap becomes smaller.

In this way, by adjusting the printing gap, the flying time is adjusted to be substantially constant regardless of the paper thickness.

Next, a method for correcting the deviation of the printing position between the forward printing direction and the reverse printing direction in the case where the moving speed of the carriage 4 can be changed to at least two types will be described. Or, after correcting the misregistration amount of the printing position in the other printing direction with reference to the printing position in the one printing direction of the reverse printing direction, the reference printing position between the different types of moving speeds The position shift amount is corrected based on a reference print position at one moving speed.

Or, conversely, a forward printing direction at another type of moving speed based on a printing position in one of the forward printing direction or the reverse printing direction at one type of moving speed among the plurality of types of moving speeds Or, after correcting the printing position deviation amount of the printing position in one of the printing directions of the reverse printing direction, the printing position in the printing direction of one of the printing directions in the forward printing direction or the reverse printing direction at the moving speed of each type described above. The correction of the print position deviation amount in the direction is executed.

If this is simply illustrated, the printing position is set based on the printing in the forward printing direction (right direction) at the moving speed V1.
MFV1, the printing position when printing in the reverse printing direction (left direction) at that speed is MRV1, and the sequential printing position MFV1 and the reverse printing position MRV1
And the print position deviation amount F1.

Further, the printing position in the forward printing direction at a moving speed V2 higher than the moving speed V1 is MFV2, the printing position in the reverse printing direction at the moving speed is MRV2, and the forward printing position MFV2
And a print position deviation amount F2 between the reverse print position MRV2 and the reverse print position MRV2.

Further, the print position deviation amount F3 between the sequential print position MFV1 and the sequential print position MFV2 is defined as F3.

In this case, there are the following two types of correction order modes.

As one of them, first, the sequential printing position at the moving speed V1
The print position and the reverse print position MR are fixed with reference to MFV1.
After correcting the print position deviation amount F1 from V1, the print position deviation amount F2 from the reverse print position MRV2 is corrected based on the forward print position MFV2 at the moving speed V2, and further, the forward print position MF
Print position deviation amount F3 from sequential print position MFV2 based on V1
Is corrected.

The other is, first, the sequential printing position MFV1 at the moving speed V1.
After correcting the print position shift amount F3 with respect to the forward print position MFV2 at the moving speed V2 based on the reference speed, the print position shift amount between the forward print position MFV1 and the reverse print position MRV1 at each of the above moving speeds.
This corrects the print position deviation F2 between F1 and the forward print position MFV2 and the reverse print position MRV2.

When correcting the printing position shift amount, the position shift amount F1, F2
The digital signal is input by manually inputting the delay times TF1 and TF2 corresponding to
The print timing is delayed (advanced) by storing it in the non-volatile memory (EEPROM) 24 and shifting the position of the interrupt signal for setting the print timing. The correction is carried out by adjusting the print area by shifting the print timing section as a whole, that is, by adjusting the print area. However, all the corrections may be performed by correcting the print area.

Hereinafter, an embodiment in which a correction value is input by operating a touch switch will be described with reference to the switch panel diagram in FIG. 5 and the flowchart (print position correction subroutine) in FIG. 6. Reference numeral 42 denotes a switch provided in the printing device. The liquid crystal display units provided on the panel 31 and denoted by reference numerals S1, S2, S3, S4, and S5 are five touch-type (press-down) switches, which are distinguished by switch numbers below. The outputs of these switches output digital signals like binary coded decimal representation codes (BCD).

The liquid crystal display unit 42 displays characters such as online mode and offline mode by pressing the switches,
This is for distinguishing the type of a ruled line matching mode, which will be described later, and for displaying a numerical value of a correction value.

When switch No. 5 in FIG. 5 is depressed, the printing apparatus enters the off-line mode. Then, when switch No. 2 is depressed and switch No. 3 is depressed, the printer enters the ruled line matching mode.

In this state, it is determined whether or not the switch No. 1 has been pressed (step 601). If the switch No. 1 is not pressed, the mode becomes the ruled line matching mode “1”. The character display of the ruled line matching mode "1" appears.

In the state of the ruled line matching mode “1”, the reverse printing position MRV1 for printing in the reverse printing direction (leftward) and the forward printing position MFV1 for the reference forward printing direction (rightward) at the moving speed V1. The correction of the print position deviation amount F1 is executed.
First, the reference order printing position MFV1 is printed with ruled lines. In this case, without pressing the switch No. 2 and the switch No. 4 (see steps 603 and 604), by pressing the switch No. 3 (step 605), the work of printing ruled lines on the paper 15 is executed (step 605). 607), when switch No. 3 is pressed again after printing a predetermined number of ruled lines, the printing operation is stopped (step 609), and the process returns to before step 601.

In this way, the operator first prints the printing position deviation amount between the reference printing position MFV1 as a reference and the reverse printing position MRV1 before correction with a ruled line, then measures this deviation amount and checks the deviation amount. I do.

Next, without depressing the switch No.1, step 603
When switch No. 2 is pressed once, the temporal correction value (time delay value T) corresponding to moving the reverse printing position MRV1 to be corrected to the left by a predetermined distance (for example, 1/180 inch).
d) is corrected, and a message to the left to move leftward by a predetermined distance (for example, one dot) corresponding to the correction value is displayed on the liquid crystal display unit (step 610).

Further, if switch No. 4 is pressed once, the temporal correction value (time delay value Td) corresponding to moving the reverse printing position MRV1 to the right by a predetermined distance (for example, 1/180 inch) is corrected. The liquid crystal display unit displays a message to the right of a predetermined distance (for example, one dot) corresponding to this correction value (step 610).

Switch No. 2 and Switch No. 4 are corrected so as to move left or right by the predetermined value each time the switch is pressed, so that the other switch is pressed a predetermined number of times when going too far in one direction By doing so, the correction value can be corrected without excess or deficiency.

Therefore, for example, switch No. 2 is pressed twice and the switch
When No. 4 is pressed five times, correction to move three dots to the right is executed as a result, and an indication to that effect appears on the liquid crystal display unit.

In response to the interrupt signal INT generated by the output of the encoder 36, the clock pulse signal C generated by the clock generation circuit built in the central processing unit 16 is converted into a print timing pulse in the forward print direction and a print timing pulse in the reverse print direction. However, the shift is made by a time delay from the interrupt signal.

The interval between the clock pulses C is defined as
For example, it is set to correspond to a shift of 1/180 inch.

Next, when the switch No. 3 is pressed once, a correction value set as a correction result obtained by subtracting according to the number of times the switch No. 2 and the switch No. 4 are pressed is stored in the EEPROM 24 so as to be registered ( Step 606), while moving the carriage 4 in the reverse printing direction in the state of the correction value, in order to print the ruled line by the print head 2, the reverse printing position MRV1 is printed at a plurality of places (Steps 607 to 609); The operator again checks whether the printing position deviation amount is within a predetermined allowable range, and repeats the above operation until the printing position deviation amount falls within the allowable range.

In this way, first, the sequential printing position at the moving speed V1
The print position and the reverse print position MR are fixed with reference to MFV1.
The printing position deviation amount F1 from V1 can be corrected.

When switch No. 1 is pressed, the process exits from the ruled line matching mode (steps 625 and 626).
reference).

When the first ruled line printing operation is completed and the ruled line matching mode is set to “2” in a state where step 1 is not pressed (steps 601 and 612), the display of the ruled line matching mode “2” is displayed on the liquid crystal display unit. Exit (step 613).

In this state, the printing position deviation amount F2 between the forward printing position MFV2 for printing in the forward printing direction (right direction) as a reference at the moving speed V2 and the reverse printing position MRV2 for printing in the reverse printing direction (left direction) is determined. In the correction, as in the case of the moving speed V1, first, the reference forward printing position MFV2 and the reverse printing position MRV2 before the correction are printed on the paper 15 with ruled lines, and then,
By pressing switch No. 2, the reverse printing position MRV2 is shifted to the right,
Alternatively, the correction value to be shifted to the left by pressing switch No. 4 is corrected (see steps 614 to 617).

The control from step 614 to step 617 is substantially the same as the control from step 603 to step 611.

Thereafter, when switch No. 3 is pressed, the above-described step 607 is performed.
In the same manner as in step 609, the correction value that has been corrected and set as a result of subtraction according to the number of times the switch No. 2 and switch No. 4 are pressed is stored in the EEPROM 24 so as to be registered (step 619). While the carriage 4 is moved in the reverse printing direction in the state of the correction value, the reverse printing position MRV2 is printed at a plurality of positions so as to print the ruled line by the print head 2 (steps 620 to 622). It is checked whether or not the print position deviation amount is within a predetermined allowable range, and the above operation is repeated until the print position shift amount falls within the allowable range. The correction of the print position deviation amount F2 between the print position MFV2 and the reverse print position MRV2 for printing in the reverse print direction (left direction) is executed.

After this check, if the ruled line matching mode is set to "3", the ruled line matching mode "3" is displayed (step 623).

In this state, the reference sequential printing position MFV1 at the moving speed V1 and the standard sequential printing position MFV2 at the moving speed V2 are set.
(Step 624). In this correction work, the printing area is shifted, and the section of the printing timing is shifted left and right (for example, from the rising edge of the printing timing). This is performed by dividing the section up to the down stream into eight sections and shifting the print timing section to the right or left for each of one or more of the divided sections.

By performing the correction in this manner, even in a printing operation in which the moving speed (printing speed) of the carriage changes for each line, the printing positions of all the lines are aligned.

If the carriage has three moving speeds, the amount of displacement of the printing position in the reverse printing direction based on the printing position in the forward printing direction at the reference moving speed is corrected, and the correction value is stored. And correcting the deviation of the printing position in the reverse printing direction from the printing position in the reference direction (for example, the right direction) corresponding to the other two types of moving speeds, storing the correction value, and further storing each moving speed. The amount of positional deviation between the reference printing positions between them can be determined as a correction of the amount of deviation from one of the reference printing positions.

The reference moving speed may be any speed, and may be based on either the forward printing direction or the reverse printing direction.

〔The invention's effect〕

As described above, not only the correction of the printing position deviation in the other printing direction with respect to the printing position in one printing direction (reference printing position) in the bidirectional printing apparatus, but also the change in the moving speed (printing speed) of the carriage. Since the amount of deviation between the reference printing positions between the different moving speeds has also been corrected, it is possible to eliminate the positional deviation of bidirectional printing at all printing speeds, especially when the printing speed can be changed for each line In addition, the printing position in any direction can be made to coincide with the reference printing position, and there is an effect that the printing quality can be remarkably improved.

In the correction work, the correction of the printing position deviation between the two directions of printing at one moving speed is first performed, and then the correction of the printing position deviation between the reference printing directions between the different moving speeds is performed. In addition, the correction can be performed in the reverse order, and the priority of the correction is not limited, so that there is an effect that the correction work is also facilitated.

[Brief description of the drawings]

1 is a front view of the printing apparatus, FIG. 2 is a side view taken along the line II-II of FIG. 1, FIG. 3 is a block diagram of the control apparatus, and FIG. FIG. 5 is an explanatory view of the panel switch, and FIG. 6 is a flowchart. DESCRIPTION OF SYMBOLS 1 ... Platen body, 2 ... Print head, 3 ... Ribbon cassette, 4 ... Carriage, 4a ... Boss part, 5 ... Support shaft, 6 ... Timing belt, 7a ... Drive pulley, 8 ...
... DC servo motor, 9 ... Step motor, 10,11 ...
Transmission gear, 12: sector gear, 13: auxiliary shaft, 14: regulating piece, 16: central processing unit, 18, 19: character generator, 24 ...
… EEPROM, 21,22 …… RAM, 23,26,29 …… Gate array,
30 …… Print head drive circuit, 35 …… Motor drive circuit, 36
… Encoder, 39… Speed switch, 42… Liquid crystal display.

Claims (2)

(57) [Claims] A carriage on which a print head disposed opposite to a platen is mounted is moved at the same speed along a forward printing direction and a reverse printing line direction, and at least two kinds of moving speeds are provided. In the printing device configured to be able to be changed to, the position of the printing position in the other printing direction based on the printing position in one of the forward printing direction or the reverse printing direction at the moving speed of each type described above A print position correction method comprising: correcting a shift amount, and correcting a position shift amount between the reference printing positions between the different types of moving speeds with reference to a reference printing position at one moving speed. Method. 2. A printing apparatus according to claim 1, wherein a carriage having a print head disposed opposite to a platen is moved at the same speed along a forward printing direction and a reverse printing line direction, and the moving speed is at least two or more. A printing apparatus configured to be able to change the printing position in one of the plurality of moving speeds in the forward printing direction or the reverse printing direction at one of the moving speeds. After correcting the printing position deviation amount of the printing position in one of the forward printing direction or the reverse printing direction at the moving speed of the type, the moving amount of the forward printing direction or the reverse printing direction at the moving speed of each type is corrected. A print position correction method, comprising correcting a print position shift amount in one direction with respect to a print position in another direction.