JPS63274575A - Printer - Google Patents

Abstract

PURPOSE:To fix intercharacter spaces in each printing line by moving a carriage to a further upper position from a printing start position in a following line with the printing direction of the following line as a reference before the start of printing in the following line after completion of printing in the existing printing line, when permitting the carriage to be moved to the printing start position of the following line. CONSTITUTION:An identification means 2 identifies whether the printing end position of each printing line identifies whether the existing printing head is positioned between the printing start position and printing and position of a following printing line, based on data of a data memory 1. Then if the identification means 2 determines that the printing end position of each printing position is set between the printing start position and printing end position, a control means 3 ends printing of the existing printing line, the carriage is allowed to move to an upper position than the printing start position of a following start position with the printing direction of a following line as a reference, and then to the printing start position of a following line. Consequently, P any adverse effect of a backlash by a drive system which drives the carriage or wire tension can be avoided, thus an intercharacter interval can be set constant.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a printing device that performs reciprocating printing in units of print lines, and in particular, when printing a document over multiple print lines, it is possible to adjust the character spacing in each print line. The present invention relates to a printing device that maintains a constant level.

[Prior art]

-a. In printing devices such as electronic typewriters and printers, when printing text data stored in a text memory or print data sent from an external device over multiple print lines, it is necessary to write data from the left margin position. In addition to those that print sequentially in one direction toward the margin position, there are some that are configured to print reciprocally in both the right and left directions in order to increase printing speed.

Furthermore, in a printing device capable of reciprocating printing, when printing the next print line, the left end print position (line start print position) and right end print position (line end print position) are calculated, and the final print position of the previous line is calculated. We have also commercialized a product that performs shortest printing control (refer to USP 3,764,994) by moving the carriage to the shortest printing start position (leftmost printing position or rightmost printing position) to further improve printing speed. has been done.

For example, when printing the first printing line (line segment F) in the right direction as shown in FIG.
Left end printing position ρ and right end printing position R of the printing line (line segment S)
If it is located between Rp and Rp, the line feed process is performed first, that is, the printing paper is advanced by the line space, then the carriage moves to the rightmost printing position Rp, and after printing the end of line character at the rightmost printing position Rp, The carriage is controlled to move sequentially to the left while printing the second line.

[Problem that the invention seeks to solve]

In the above-mentioned printing devices capable of reciprocating printing, ingenuity has been put into control to improve the printing speed, including those that control printing in the shortest possible time. For example, when printing the first printing line in the right direction as shown in Figure 8, move the carriage from the final printing position Ep to the rightmost printing position Rp, print the end of line character at the rightmost printing position Rp, and then move the carriage sequentially. When printing the second line while moving to the left, the character at the end of the line is printed with the carriage driven to the right, but each character other than the last character is printed with the carriage driven to the left. It will be printed.

In other words, the character spacing between the last character and the next printed character becomes smaller than the character spacing of other characters due to backlash in the drive system that drives the carriage, wire tension, etc., and the character spacing on the same line becomes smaller. There is a problem in that the characters are not constant, and the characters in the upper and lower lines are also misaligned, making it impossible to print documents neatly.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a printing device that can make the character spacing in each print line constant when printing a plurality of print lines back and forth in print line units.

[Means for solving problems]

As shown in the functional block diagram of FIG. 1, the printing device according to the present invention includes a data memory for storing print data of characters and symbols, and a print head mounted on a carriage, which prints the print data while moving together with the carriage. It is equipped with a printing means for printing on a printing medium, and a reciprocating printing control means for controlling the printing means to perform reciprocating printing while appropriately moving a carriage in the forward direction and backward direction in units of print lines when printing print data. In a printing device, whether or not the print end position of each print line corresponding to the current print head is located between the print start position and print end position of the next print line, based on data in the data memory. and, based on the determination result of the determining means, after the completion of printing of the current print line and before the start of printing of the next line, a position higher than the print start position of the next line based on the printing direction of the next line is determined. After the carriage is moved to the side, a control means is provided for moving the carriage to the printing start position of the next line.

Note that, if necessary, the control means may include backlash correction means for correcting backlash of the drive means for driving the carriage.

[Effect]

In the printing device according to the present invention, print data of characters and symbols is stored in the data memory, and the printing means prints the print data on the print medium while moving the print head together with the carriage. At this time, the printing means is controlled to perform reciprocating printing while appropriately moving the carriage in the forward and backward directions in units of print lines.

Further, the determining means determines whether the print end position of each print line corresponding to the current print head is located between the print start position and print end position of the next print line based on the data in the data memory. It is determined.

When the determining means determines that the print end position of each print line is located between the print start position and print end position of the next print line, the control means terminates printing of the current print line. , the hexeridge is further moved higher than the print start position of the next line based on the print direction of the next line, and then moved to the print start position of the next line.

That is, in each printing line, each character from the print start position to the print end position is printed in the same direction while the carriage moves in the forward or backward direction, so backlash of the drive system that drives the carriage and wire Effects such as tension are avoided, and the character spacing between each character becomes constant.

〔Effect of the invention〕

As explained above, according to the printing device according to the present invention,
Each character' in each printing line is printed in the same direction while moving the carriage in the forward or backward direction.
Since the effects of backlash in the carriage drive system and wire tension are avoided, the spacing between each character from the print start position to the print end position is reliably constant unless the print pitch is changed, resulting in a good-looking and clean print. You can print documents.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

This embodiment is a case where the present invention is applied to an electronic typewriter.

As shown in FIG. 2, a keyboard 3 is arranged at the front of the main body frame 2 of the electronic typewriter 1, a printing mechanism PM is arranged on the main body frame 2 behind the keyboard 3, and the keyboard 3 A one-line liquid crystal display 75 is provided at the rear of the screen to display input characters, symbols, etc.

The keyboard 3 is provided with character keys 10 including alphabet keys, numeric keys, and symbol keys, a print start key 11 for printing text data in the text memory 52, and various function keys as in a normal typewriter. .

The printing mechanism PM includes at least a platen 20 that feeds printing paper, a motor that drives the platen, and a drive circuit thereof.
A carriage 22 supported by a guide 21 parallel to the platen 20, a carriage drive motor and a carriage drive circuit that drive it back and forth in the left-right direction, a type wheel 24 housed in a wheel cassette 23, a motor that drives it, and its drive circuit. , the printing ribbon 26 stored in the ribbon cassette 25, the motor that winds it and its drive circuit, the printing hammer that hits the type 27 of the type wheel 24, the solenoid 28 that drives it and its drive circuit, the printing ribbon 26.
Alternatively, a ribbon switching mechanism for selectively arranging the correction ribbon 29 at a printing position is provided, and this printing mechanism PM
is similar to the printing mechanism of a normal electronic typewriter.

Next, the overall configuration of the control system of the electronic typewriter I will be explained based on the block diagram of FIG.

The electronic typewriter 1 basically consists of a keyboard 3, a printing mechanism PM, a display mechanism, a control device C, etc. The keyboard 3, printing mechanism PM, display mechanism are connected to the main controller C via a data bus, etc. CPU (central processing unit) 39
It is connected to the.

The control device C includes a main CPU 39 and its main CPU 3.
9 through a data bus etc.
RAM (Random Access Memory) 40 and RAM (Random Access Memory) 50.

The program memory 41 of the ROM 40 includes the keyboard 3.
A control program for controlling the printing mechanism PM and display mechanism in correspondence with code data input from each character key 10 and various function keys, a control program for reciprocating printing control to be described later, and the like are stored.

The RAM 50 includes a current position memory 51 that sequentially updates and stores the current position of the carriage 22 (print head) from the absolute origin in correspondence with the print position, and data such as characters printed in the typewriter mode. A print data memory that stores approximately 500 characters in sequence in correspondence with the print position;
an input buffer that stores data such as characters input from the keyboard 3 or successively output from the text memory 52 during the memory mode (display mode); a text memory 52 that stores the input data as file data;
A cursor display position counter that associates the cursor display position with each display position on the display 75 and counts according to the movement of the cursor; a cursor position pointer that indicates the address of the input buffer in accordance with the data of the cursor display position counter; and the main CPU 39. In addition to various memories that temporarily store the results of arithmetic processing in the text memory 52, it is set when printing text data in the text memory 52 in the right direction (right margin direction), and is set in the left direction (right margin direction).
The print direction flag 53 is reset when printing in the left margin direction), and when the print start key 11 is operated, one print line of text data to be printed is sequentially read from the text memory 52 or an external device and stored. A buffer 54, a left margin position memory for storing a set left margin position, a pitch memory for storing a set printing pitch, and the like are provided.

Note that an EOT (end of text) code is stored in the text memory 52 after the final data of the text data.

Based on the control program, the main CPU 39 causes the printing mechanism PM to print characters and symbols corresponding to data input from each character key 10, and sequentially stores the print data in the print data memory in correspondence with the print position. Furthermore, when in the memory mode, the main CPU 39 stores input data for one print line in the input buffer and displays it on the display 75, and stores the data for one line in the text memory 52 in response to the operation of the return key 12. Make me remember.

The display mechanism consists of an interface 70 and a CPIJ for display.
71, a character generator 72, a display controller 73, and a liquid crystal display 75.
Connected as shown.

Note that the display mechanism is the same as a known one and has no direct relation to the present invention, so a description thereof will be omitted.

Next, the reciprocating printing control performed by the control bag 2c of the electronic typewriter 1 will be explained based on the flowchart shown in FIG.

This control will be explained with reference to FIGS. 5(a) to 5(j). In this figure, line segment F indicates the printing position on the first line, and line segment S indicates the printing position on the second line. Also, E, is the final printing position of the first printing line, LP is the left end printing position of the second printing line (printing position at the beginning of the line), R, is the rightmost printing position of the second printing line (printing position at the end of the line), and the dotted line is Print paper advance, arrow ``
-" indicates rightward movement of the carriage, and arrow "=" indicates leftward movement of the carriage.

When the typewriter 1 is powered on, this control starts and moves to step Sl (hereinafter simply referred to as Sl, and other steps are handled in the same way), where the first line is printed in the right direction. Initial settings such as setting the direction flag 53 (printing direction flag data "1") are performed, and the process waits for key input in S2. When the key is pressed, the process moves to S3.

In S3, it is determined whether or not the print start key 11 is pressed, and if it is the print start key 11, the process moves to S4. In S4, text data for the first one print line is read from the text memory 52 and written to the print buffer 54.
At step 5, it is determined whether or not there is text data based on the data of the text memo 1J52, and if there is text data, the process moves to S6. In S6, the first data of the text data is printed as characters. Incidentally, after printing a character, the print head is moved to the right by one character. At this time, the main CPU 39 outputs control signals to each drive circuit of the printing mechanism PM.

Next, in S7, the next data to be printed is read from the print buffer 54. In S8, it is determined whether the read data is end data, that is, an EOT code, and if it is not an EOT' code, the process moves to S9. S
At step 9, it is determined whether the data is the last data in the row, that is, whether it is the data immediately before the return code, and if the answer is No, the process returns to S6. Then, steps 56 to S9 are repeated and, for example, when the data of one character before the final printing position WE of the line segment F shown in FIGS.
It is determined that the process moves to S10. In S10, the final data of the line is printed at the final print position fE. Furthermore, at this time,
The print head is at the final print position Ep.

At Sll, text data for the next print line is read out based on the text data in the text memory 52 and written into the print buffer 54.

In S12, the left end printing position LP and right end printing position R of the line segment S in the next line are calculated based on the data in the current position memory 51, the data in the print buffer 54, and the data in the pitch memory, and the final printing position is calculated. It is determined whether the print position E is located between the left end print position and the right end print position R2, and if Yes, that is, the carriage 22
For example, as shown in FIGS. 5(b) and 5(e), the final printing position Ep is the left end printing position t, p of the line segment F and the right end printing position. It is located between Rp.

In S13, from the final printing position Ep to the left end printing position t, p
It is determined whether the absolute value obtained by subtracting is smaller than the absolute value obtained by subtracting the right end printing position Rp from the final printing position Ep. If Yes, that is, the carriage 22 is moved to the final printing position WE.
If it is closer to move to the left end print position t, p than to move from p to the right end print position Rp, the process moves to S14 (
(shortest printing control). For example, there is a case shown in FIG. 5(e).

In S14, the print head (carriage 22) is
is moved one character bone above the left end printing positions t and p (towards the left margin). In the next step 515, line feed processing such as feeding the printing paper by the set line space is performed. Furthermore, in S16, the print head is moved to the left end printing position '11 Lp (see FIG. 5(e)).

In S17, based on the data of the printing direction flag 53, it is determined that the previous printing was not in the right direction.
It is determined whether the data of the flag 53 is "1" or not. In this case, the data of the flag 53 is "1" and the process returns to step S6. Also, if the data of the printing direction flag 53 is rl, the process moves to 318, and the data of the flag 53 is inverted (when the flag data is "1", it becomes "0", and when it is "o", it becomes "1"). ) and returns to S6.

On the other hand, when the determination in 313 is No, that is, the carriage 2
When it is closer to move 2 from the final print position Ep to the right end print position Rρ than to the left end print positions t, p, the process moves to 319.0 For example, in the case shown in FIG. 5(b).

In S19, the right end printing position MRp and the current position memo IJ51
The print head is moved from the right end printing position WRp to the upper side of the character bone (in the direction of the right margin) based on the data of 0.
In the next step 320, line feed processing such as feeding the printing paper by the set line space is performed. At 321, the print head is moved to the rightmost printing position Rp (FIG. 5(b)
reference).

Then, in S22, it is determined whether or not the previous printing was in the right direction. If it was in the right direction, the process moves to 31B, and if it was in the left direction, the process returns to S6.

When it is determined No in step 512, that is, when it is determined that the final printing position E is not located between the leftmost printing position fL and the rightmost printing position R, backlash correction of the carriage 22 is required. For example, as shown in FIGS. 5(a), (c), and (d),
Final print position E.

is not located between the left end printing position Lp and the right end printing position Rp of the line segment F.

323, the absolute value obtained by subtracting the left end printing position WLp from the final printing position Ep is the right end printing position W from the final printing position Ep.
It is determined whether or not it is smaller than the absolute value obtained by subtracting Rp, and if Yes, that is, the carriage 22 is moved to the final printing position ffE.
3 when moving from p to the left end printing position Lp is closer than moving to the right end printing position WRp (shortest printing control I).
For example, this is the case shown in FIG. 5(d). Further, when the determination is No, that is, when it is closer to move the carriage 22 from the final printing position Ep to the rightmost printing position Rp than from the leftmost printing position P, the process moves to S20. For example, as shown in FIG. 5(a), This is the case shown in (C).

Then, when the printing direction is leftward and flag data "0" is written in the printing direction flag 53, control is performed through steps 36 to S23 in the same way as when printing is rightward.

That is, for example, in the case of FIG. 5(g), reciprocating printing is controlled including backlash correction of the carriage 22 through steps 86 to S18, and in the case of FIG.
Through steps 9 to S22, reciprocating printing is controlled including backlash correction of the carriage 22. Also, Fig. 5 (f), (h
), reciprocating printing is controlled through steps S6 to S12, S23, and S15 to S18 without backlash correction of the carriage 22, and further, in the case of FIG.
- Through S23 and S20 to S22, reciprocating printing is controlled without backlash correction of the carriage 22.

When all the text data in the text memory 52 has been printed, a YES determination is made in S8, and the process moves to S24, where printing termination processing such as clearing the data in the print buffer 54 is performed, and the process returns to S2.

Note that if the determination is No in S5, the process moves to 525, where an alarm process such as sounding a buzzer is performed, and the process returns to S2. or,
When the determination in S3 is NO, that is, when a key other than the print start key 11 is operated, the process moves to S26, the process corresponding to the operated key is executed, and the process returns to S2.

As explained above, when performing reciprocating printing for multiple lines including shortest printing control, if the final printing position is located between the leftmost printing position and rightmost printing position of the next printing line, When moving the print head to the left end printing position, the print head is moved one character above the left end printing position, and then moved to the left end printing position, and when moving the print head to the right end printing position, the print head is moved to the right end printing position. After moving one character above the position, it moves to the right end printing position, so each printing character in each printing line is printed in the same direction. That is, the character spacing between each character on the same line is constant, and it is possible to print a document neatly.

In the above embodiment, in order to correct backlash, when moving the Rad to print, it is moved by one character, and then one character is moved to the normal position. It is not limited to characters, and in short, any movement amount sufficient to correct the backlash of the carriage may be used.

Furthermore, although the above embodiments have been described with respect to reciprocating printing in units of print lines, it goes without saying that the present invention can be similarly applied to movement of the carriage after cover oven processing.

[Second Embodiment] In the reciprocating printing control in the above embodiment, when the printing direction is reversed and the next print line is printed, the carriage is moved an extra predetermined amount, and then the carriage is returned in the opposite direction by a predetermined amount. This prevents the effects of backlash and keeps the character spacing constant, but in reality, when the printing direction is reversed and the next printing line is printed, each character is different between the current printing line and the next printing line. A misalignment occurs in the printing position. In other words, each print position that is printed in the right direction and then printed in the left direction is shifted to the right from the print position that is printed in the right direction.

Further, after printing in the left direction, each print position printed in the right direction is shifted to the left from the print position printed in the left direction.

In order to avoid this positional deviation, the reciprocating printing control routine in the above embodiment is partially changed as shown in FIG. 6, and when the printing direction is reversed after the backlash correction described above, The amount of rotation of the carriage drive motor, that is, the amount of backlash correction, is controlled so that the print position of each character printed in the right direction (right direction) corresponds to the print position of each character printed in the right direction (left direction). may be configured.

That is, the reciprocating printing control routine of this second embodiment will be explained based on the flowchart of FIG. 6.
Then, the data of the printing direction flag 53 is inverted, and the process moves to S30. At S30, the data of the printing direction flag 53 is “
It is determined whether or not the printing direction has been reversed from "1" to "0", that is, whether the printing direction has been reversed from rightward printing to leftward printing, and if Yes, the process moves to 331. At S31, the carriage 2 is not rotated despite the rotation of the carriage drive motor.
2 is the rotation amount of the carriage drive motor that does not actually move (
The carriage drive motor is driven to rotate in the opposite direction by the amount of backlash correction (backlash correction amount), and the print head is moved a predetermined distance to the left, and the process moves to S6.

When the determination is NO in S30, that is, the printing direction flag 5
When the data of 3 is reversed from "0" to "IJ",
The process moves to S32. In S32, the carriage drive motor is rotated forward by the amount of backlash correction, and the print head is moved a predetermined distance to the right, and the process proceeds to S6.

Thereby, the carriage 22 can print characters at a predetermined position with no apparent upward positional deviation. The backlash correction amount is calculated by measuring the actual positional deviation distance.
0 may be stored as data, or may be set arbitrarily by the operator.

This reciprocating printing control routine is not limited to the flowchart shown in FIG. 4 or FIG. 6, but may be changed to the routine shown in FIG. 7.

In the above embodiment, an electronic typewriter equipped with a type wheel type printer has been described, but it goes without saying that the present invention is equally applicable to typewriters equipped with a thermal printer, a shuttle type printer, and a dot matrix type printer. stomach.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram explaining the present invention in detail;
5 to 5 show embodiments of the present invention, FIG. 2 is a perspective view of an electronic typewriter, FIG. 3 is a block diagram of the typewriter control system, and FIG. 4 is a flowchart of the printing control routine. , FIG. 5 is a diagram for explaining reciprocating printing control, FIG. 6 is a partial diagram corresponding to FIG. 4 of the second embodiment, and FIG. 7 is a partial diagram corresponding to FIG. 4 according to a modification of the second embodiment. FIG. 8 is a diagram illustrating conventional reciprocating printing control. 11...Print start key, 22...Carriage, 39
...Main CPU, 40...ROM. 50...RAM, 51...Current position memory, 52...
Text memory, 53...Print direction flag, C...
Control device, PM...printing mechanism. Figure 6 Figure 7

Claims (2)

[Claims] (1) A data memory that stores print data of characters and symbols; a printing means that prints print data on a print medium while moving a print head mounted on a carriage with the carriage; and a reciprocating printing control means for controlling the printing means to perform reciprocating printing while appropriately moving the printing line in the forward and backward directions in units of printing lines. a determining means for determining whether or not a print end position of each print line corresponding to the head is located between a print start position and a print end position of the next print line, based on the determination result of the determination means; , After the current printing line is completed and before the next line starts printing, move the carriage further above the next line's printing start position based on the next line's printing direction, and then set the next line's print start position. A printing device characterized in that it is provided with a control means for moving the printing device. (2) The printing apparatus according to claim 1, wherein the control means includes backlash correction means for correcting backlash of the drive means for driving the carriage.