JPH0671811B2 - Character erasable printing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character erasable printing device, and particularly, when erasing an underlined character, according to the underline information of the printed character before and after the erased character. The present invention relates to a character erasable printing device.

(Prior Art) In general, some printers such as electronic typewriters capable of erasing characters are equipped with an autocorrection mechanism for erasing erroneously printed characters during printing by operating an erasing key. As the autocorrection mechanism, there are a cover wrap method in which a correction agent is stuck on the printed characters and a lift-off method in which the printed ink is peeled off with a correction ribbon. In recent years, the lift-off method is generally used.

In the lift-off method, the ink printed on the printing paper is peeled off by the printing ribbon to erase the erroneously printed characters, so that the printing element is required to be in the same position during printing and during erasing. That is, if the positions of the printing elements during printing and erasing deviate from each other even a little, a portion of the printed ink that cannot be stripped occurs. In order to completely erase erroneously printed characters, it is required that the printing elements be at the same position during printing and during erasing. However, obtaining such position accuracy has a mechanical and cost limit.

Then, conventionally, for example, Japanese Patent Publication No. 56-46992 and Japanese Patent Laid-Open No. 60
In Japanese Patent Laid-Open No. 147376, in a printing apparatus adopting a lift-off method, an erroneous printing character is completely stripped off by performing an erasing operation a plurality of times while moving a carriage laterally by a small amount.

(Problems to be Solved by the Invention) In the above conventional printer, when characters with lander lines are printed in the auto underline mode, if the characters with underlines are erased by the autocorrection function, Underline can be erased at the same time.

At this time, as described above, the printing apparatus moves the carriage to the left and right by a small amount to erase the erroneous printed characters, and also moves the carriage to the left and right by a small amount when erasing the underline. Although it can be completely erased, the underline is erased by the amount of minute movement in addition to one erased character. For this reason, as shown in FIG. 7, when the correction printing with the underline after erasure (character “H”) is performed, the underline 80 is interrupted with a gap 81 corresponding to the minute movement amount of the carriage. Therefore, there is a problem in that it becomes impossible to print clean underline that is continuous with the front and back underlines.

(Object of the Invention) An object of the present invention is to erase an underlined print character according to the underline information of the print characters before and after the erased character so that the underline can be erased. A printing device is provided.

(Means for Solving Problems) A character erasable printing device according to the present invention includes a printing mechanism for printing on a printing medium based on input data, as shown in a functional block diagram of FIG. A print data memory that stores this print data and underline information for the print data, a current position memory that stores the current position of the print head of the print mechanism, and a small amount of movement of the print mechanism in response to an erase command signal In a character erasable printing device having an erasing mechanism for erasing a printed character by operating at a position, when an erasing command signal is received, upper and lower data of the instructed printing position is stored by the current position memory. Is equipped with a judgment means for judging whether or not is underlined, and at least one of the print data on both sides is underlined by the judgment means. At the time of
Even if the erased character has an underline, the erase mechanism is provided to erase only the character by the erase mechanism without erasing the underline.

(Operation) In the character erasable printer according to the present invention, the printing mechanism prints on the print medium based on the input data, and the printed print data and the underline information for the print data are stored in the print data memory. The current position of the print head of the printing mechanism is stored in the current position memory. The erasing mechanism moves the printing mechanism by a minute amount in response to the erasing command signal and operates at a plurality of positions to erase the printed characters.

When the erasing command signal is received, the judging means judges, based on the data in the current position memory, whether the upper and lower data of the designated printing position are underlined. When at least one of the print data on both sides is underlined, the erasure control means
Even if the erased character has an underline, only the character is erased by the erasing mechanism without erasing the underline.

(Effects of the Invention) According to the character erasable printing device of the present invention, as described above, when at least one of the print data on the upper side and the lower side of the erased character is underlined, the underline Since only the characters are erased without erasing, it is possible to perform a clean underline that is continuous with the underlines before and after.

Further, since it is not necessary to print the underline again when performing the correction printing, the printing ribbon can be saved and the time for reprinting the underline can be saved.

(Example) Hereinafter, the Example of this invention is described based on drawing.

In this embodiment, the present invention is applied to an electronic typewriter.

As shown in FIG. 2, the body frame 2 of the typewriter 1
A keyboard 3 is arranged in the front part of the keyboard 3, a printing mechanism PM is arranged in the main body frame 2 behind the keyboard 3, and a keyboard 1 is provided on the rear part of the keyboard 3 for displaying input characters and symbols. A row of liquid crystal displays 75 are provided.

The keyboard 3 is provided with a character key 10 including alphabetic keys, numeral keys and symbol keys, a space key 11, a collection key 12 for erasing print characters, an auto-underline key 13 for underlining, etc. There is. The other keys have the same function as a normal typewriter.

The printing mechanism PM includes at least a platen 20 for feeding a printing sheet, a motor for driving the platen 20, a drive circuit for the platen 20, a carriage 22 supported by a guide 21 parallel to the platen 20, and a motor for reciprocating the carriage 22 in the left-right direction. And its drive circuit, the type wheel 24 accommodated in the wheel cassette 23, the motor for driving it and its drive circuit, the print ribbon 26 accommodated in the ribbon cassette 25, the motor for winding it and its drive circuit, the type wheel 24 The printing hammer for striking the type 27, the solenoid 28 for driving it, its drive circuit, the ribbon switching mechanism for selectively arranging the printing ribbon or the correction ribbon 29 at the printing position, and the like are provided.
Is similar to the printing mechanism of a normal electronic typewriter.

Next, the overall configuration of the control system of the electronic typewriter will be described with reference to the block diagram of FIG.

The typewriter 1 basically has a keyboard 3 and a printing mechanism P.
It is composed of M, a display mechanism D, a control device C and the like. The keyboard 3, the printing mechanism PM, and the display mechanism D are connected to the main CPU (central processing unit) 40 of the control device C via a data bus or the like.

The control device C comprises a main CPU 40, a ROM (read only memory) 50 and a RAM (random access memory) 60 connected to the main CPU 40 via a data bus or the like.

In the program memory 51 of the ROM 50, there are a control program for controlling the printing mechanism PM and the display mechanism D corresponding to the code data input from each character key and various function keys of the keyboard 3, a character deletion control program described later, and the like. Remembered

The RAM 60 has a current position memory 61 that sequentially updates and stores the current position of the carriage 22 (print head) from the absolute origin in association with the print position, printed character data and attribute data such as underline and bold. Print data memory 62 for sequentially storing about 500 characters in 2 bytes corresponding to the print position, an input buffer for storing data such as characters input from keyboard 3 and displayed on display 75, and display 75. Cursor display position counter that counts according to the movement of the cursor corresponding to each display position of, the cursor position that indicates the address of the input buffer corresponding to the data of the cursor display position counter, and the auto-underline mode are set And the underline mode flag 63 that sets A print data pointer 64 for retrieving dress data, various memories for temporarily storing results of arithmetic processing by the main CPU 40, and the like are provided.

Main CPU40, based on the control program, each character key 1
Characters / symbols corresponding to data input from 0 are printed on the printing mechanism PM, and the print data is sequentially stored in the print data memory 62 in correspondence with the print position. Further, when the correction key 12 is operated, the character 27 which is the same as the character to be printed based on the data in the print data memory 62 is struck through the correction ribbon 29 three times for each minute movement of the carriage 22 to print. The character is erased.

The display mechanism D includes an interface 70, a display CPU 71, a character generator 72, and a display controller 73.
And a liquid crystal display 75, which are connected as shown. The character generator 72 stores about 400 types of dot matrix display data corresponding to code data for displaying characters and symbols on the display 75. Based on the command data and character data output from the main CPU 40 via the interface 70, the display CPU 71 reads the display data corresponding to these from the character generator 72 and outputs the display data to the display controller 73. The display controller 73 writes the display data in the display RAM 74 and, at the same time, outputs a display signal corresponding to the display data to the display 75.

Next, the character erasing control performed by the control device C of the electronic typewriter will be described with reference to the flowchart of FIG.

When the power of the typewriter 1 is turned on, this control is started, and in step S1 (hereinafter, simply expressed as S1 and other steps are treated similarly), initialization such as resetting the underline mode flag 63 is executed. , S2. In S2, keep key input, and if there is key input, S3
Move to. In S3, it is determined whether the input key is the character key 10 or the space key 11, and if Yes, the next S
At 4, it is determined whether the auto underline mode is set, that is, whether the underline mode flag 63 is set. When the auto underline mode is not set (when the auto underline flag 63 is reset)
Move to S5. In S5, normal character printing without underlining corresponding to the input data is performed, and the process proceeds to S7.

When the automatic underline mode is set in S4, the process proceeds to S6, the character corresponding to the input data is printed with underline, and the process proceeds to S7. Incidentally, S6
In (1), when an underline has already been printed at the print position, an underline stop control means may be provided to prevent overprinting of the underline and prevent overprinting of the underline. , Japanese Patent Application No. 61-138625). In S7, the print data corresponding to the input key is stored in the print data memory 62.
When the underline is added in S6, the print data including the underline print data is stored in the print data memory 62, and the process returns to S2. For example, as shown in FIG. 5 (a), S2 to S4 and S6 to S7 are repeated, and the character string "ABC" is printed with underlining.

When the collection key 13 is operated, the process proceeds to S8 via S2 to S3. When it is determined as Yes in S8, the process proceeds to S9, and the data of the address corresponding to the print head position of the print data memory 62 is read based on the data of the current position memory 61. Then, in the next S10, it is determined whether or not the data is character data (including underlined space data), and if it is character data, the process proceeds to S11.

In S11, the data in the current position memory 61 is written in the print data pointer 64, and the print data in the print data memory 62 which is obtained by subtracting 1 from the data in the print data pointer 64 (the print data on the upper side of the print head position, which is one upper side). ) Is read,
Next, the print data (print data one lower than the print head position) in the print data memory 62 obtained by adding 2 to the print data pointer 64 is read. At the next step S12, whether there is underline data in the print data before and after read, that is, whether the underline addition bit provided in the lower 1 byte of one character data of the print data memory 62 is 1 or not. If it is 0, and if there is underlined data, the process proceeds to S13. In this state, for example, as shown in FIG. 5 (a), the print head is positioned at the print position of the character "B", and the print character "A" and the print character "A" one level higher than the print head position. An underline is printed on the side of the print character "B".

In S13, the print data excluding the underline data is deleted from the print data memory 62 based on the data in the current position memory 61 and the data in the print data memory 62. At this time, based on the character code of the print data excluding the underline data, the type wheel 24 of the printing mechanism PM,
The solenoid 28, the correction ribbon 29, etc. are driven, and the erasing operation is performed a plurality of times while displacing the carriage 22 by a small amount to the left and right to erase a predetermined character. More specifically, first, the correction ribbon 29 is placed at the printing position, and the same type 27 as the character to be erased is placed at the strike position. Then, the solenoid 28 is operated to strike the type 27, and the printing ink is stripped off by the correction ribbon 29. Next, move the carriage 22 to the right 0.2 mm (1/1
20 inches) and perform the same erase operation as above. Further, the carriage 22 is moved to the left by 0.4 mm (2/120 inch) and the erasing operation is performed again. When this erasing operation is completed, the carriage 22 is moved to the right by 0.2 mm, the carriage 22 is returned to the original position, the lifted correction ribbon 29 is lowered, and the erasing process is completed. 60-147376
No.). For example, as shown in FIG. 5B, only the character "B" is deleted. In the next S14, the character code of the erased print data is erased in the print data memory 62, the space code is written, and the process returns to S2.

Then, when printing characters at the erase position, if S2 to S4 and S6 to S7 are currently in the automatic underline mode.
After that, the correction character is printed without printing the underline again. For example, as shown in FIG. 5 (c), only the correction character "C" is printed.

On the other hand, if No is determined in S12, the process proceeds to S15. For example, as shown in FIG. 6 (a), when the underline is printed only on the character "B" in the character string "ABC" and the print head is located at the character "B" position. is there.

In S15, the print character (including the underline) is erased based on the data in the current position memory 61 and the data in the print data memory 62. That is, based on the character code and attribute data of the print data, the printing mechanism PM
The character wheel (24), solenoid (28), correction ribbon (29), etc. are driven, and a predetermined character (including underline) is erased by performing the erasing operation a plurality of times while moving the carriage (22) by a small amount to the left and right. The erase operation is the same as in S13.
The erase operation is performed three times with a minute change in position. When the erasing process is completed, the process proceeds to S16, the erased print data is erased from the print data memory 62, and the process returns to S2.

For example, as shown in FIG. 6 (b), the character "B" is erased together with the underline. Then, when printing characters at that position, if the underline mode
Correction printing is performed with an underline through S4, S6 to S7, and if it is not underline mode, the correction character "D" is corrected and printed through S2 to S5 and S7, as shown in FIG. 6 (c). To be done.

If it is determined No in S10, the process proceeds to S17, it is determined whether or not the data is the first data in the print data memory 62, and if it is the first data in the print data memory 62, character deletion is impossible. The alarm is processed in S19 and the process returns to S2. If the print data is not the head data in the print data memory 62 in S17, the process proceeds to S18. S18
Then, the data of the current position memory 61 and the print data memory 62
Then, the carriage 22 is moved by one character in the reverse printing direction based on the above data, and the process proceeds to S9. That is, S9 ~ S10 / S17 ~ S1
8 is repeated, and unless character deletion becomes impossible, the characters are sequentially searched in the reverse print direction until the character data is detected.
As a result, even if the print head is at the position after the tab operation or the space operation, the character data can be automatically detected.

In addition, character key 10, space key 11, collection key 12
If any key other than is operated, the judgment result of S8 is No,
In S20, a process corresponding to the operated key, for example, a process of setting or canceling the auto underline mode is executed, and the process returns to S2.

As described above, when at least one of the print characters before and after the erased character (one print character in the opposite print direction and one print character in the print direction) is underlined, only the erased character is erased and the underline is erased. Since it does not, the underline is not interrupted and continuous and clean underline printing can be performed.

[Brief description of drawings]

FIG. 1 is a functional block diagram of the printer of the present invention, and FIGS.
FIG. 6 shows an embodiment of the printer according to the present invention.
FIG. 2 is a perspective view of the typewriter, FIG. 3 is a block diagram of a control system of the typewriter, FIG. 4 is a flowchart of a control routine, and FIGS. 5 and 6 are diagrams showing print / erase states,
FIG. 7 is a diagram showing a conventional erasing state. 3 ... Keyboard, 12 ... Collection key, 29 ... Correction ribbon, 40 ... Main CPU, 50 ... ROM, 60 ... RAM, 6
1 ... Current position memory, 62 ... Print data memory, 63 ...
… Underline mode flag, C… Control unit, PM…
... printing mechanism.

Claims (1)

[Claims] 1. A print mechanism for printing on a print medium based on input data, a print data memory for storing the print data and underline information for the print data, and a current position of a print head of the print mechanism. The current position memory to be stored and the printing mechanism is moved by a small amount according to the erase command signal,
In a character erasable printing device having an erasing mechanism for erasing printed characters by operating at a plurality of positions, when the erasing command signal is received, the current position memory causes the upper and lower positions of the instructed printing position. If the erasure character is underlined even if at least one of the print data on both sides is underlined, A character erasable printing device, comprising: an erasing control means for erasing only characters by the erasing mechanism without erasing the characters.