JPS63178072A - Character erasable printer - Google Patents

Abstract

PURPOSE:To erase a character without interrupting an underline, by a method wherein only the character is erased without erasing the underline when at least one of the higher rank and lower rank side printing data of the character to be erased is provided with the underline. CONSTITUTION:It is judged whether underline data is present or not in read front and rear printing data, that is, whether the bit with an underline provided to the lower rank one bite of one character data of a printing data memory is 1 or 0 and, when the underline data is present, the next operation is taken. Then, on the basis of the data of a present position memory and the data of the printing data memory, printing data from which underline data is removed is erased from the printing data memory. At this time, on the basis of the character code of the underline data removed printing data, the type wheel 24, solenoid 28 and correction ribbon 29 of a printing mechanism PM are driven and erasing operation is performed plural times while a carriage 22 is moved left and right by minute quantity to erase a predetermined character.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a printing device capable of erasing characters, and in particular, when erasing underlined characters, the present invention is based on the underline information of the printed characters before and after the erased character. The present invention relates to a printing device capable of erasing characters.

(Prior Art) Generally, some printing devices such as electronic typewriters that are capable of erasing characters are equipped with an auto-correction mechanism that erases erroneously printed characters during printing by operating an erase key. There are two auto-correction mechanisms: a cover wrap method in which a correction agent is pasted onto the erroneously printed characters, and a lift-off method in which the printed ink is removed with a correction ribbon.The lift-off method has been commonly used in recent years.

In this lift-off method, the ink printed on the printing paper is removed with a printing ribbon to erase erroneously printed characters, so the printing element is required to be in the same position during printing and erasing. That is, if the position of the printing element during printing and erasing is even slightly shifted, a portion of the printed ink will not be peeled off. In order to completely erase erroneously printed characters, it is required that the printing element be in exactly the same position during printing and erasing. However, obtaining such positional accuracy has mechanical and cost limitations.

Therefore, conventionally, for example, in Japanese Patent Publication No. 56-46992 and Japanese Patent Application Laid-Open No. 60-147376, in a printing device adopting a lift-off method, the erasing operation is performed multiple times while moving the carriage by a minute amount left and right. , the ink from misprinted characters can be completely removed.

(Problems to be Solved by the Invention) In the conventional printing device described above, when an underlined character is printed in the auto underline mode, if the underlined printed character is erased by the auto correction function, Underlines can also be deleted at the same time.

At this time, as mentioned above, the printing device moves the carriage a small amount left and right to erase the erroneously printed characters, and also moves the carriage a small amount left and right when erasing the underline, so the erroneously printed characters are removed. Although it can be completely erased, the underline will be erased by the amount of minute movement in addition to one character to be erased. For this reason, as shown in FIG. 7, when correct printing with an underline (letter "H") is performed after erasing, the underline 80 is interrupted by a gap 81 corresponding to the minute movement of the carriage. Therefore, there is a problem in that it is not possible to print beautiful continuous underlines between the front and rear underlines.

(Objective of the Invention) An object of the present invention is to erase a printed character with an underline according to the underline information of the printed characters before and after the erased character, so that the character can be erased without interruption of the underline. The purpose of the present invention is to provide a printing device.

(Means for Solving the Problems) As shown in the functional block diagram of FIG. 1, the character-erasable printing device according to the present invention includes a printing mechanism that prints on a printing medium based on manually inputted data; A print data memory stores this print data and underline information for the print data, a current position memory stores the current position of the print head of the print mechanism, and a print mechanism is moved by a minute amount in response to an erase command signal. In a character-erasable printing device that has an erasing mechanism that erases printed characters by operating it at a certain position, when an erasing command signal is received, the current position memory stores the upper and lower data of the designated printing position. is provided with a determination means for determining whether or not is underlined, and the determination means determines that when at least one of the printed data on both sides is underlined,
Even if the erased character has an underline, it is provided with an erase control means for erasing only the character without erasing the underline using an erasing mechanism.

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

Upon receiving the erase command signal, the determining means determines whether or not the upper and lower data of the designated printing position are underlined, based on the data in the current position memory. When at least one of the printed data on both sides is underlined, the erasing control means causes the erasing mechanism to erase only the character without erasing the underline even if the erased character has an underline.

(Effects of the Invention) According to the character erasable printing device according to the present invention, as explained above, when at least one of the print data on the upper side and the lower side of the erasable character is underlined, Since only the characters are erased without erasing the characters, it is possible to print a beautiful continuous underline between the previous and subsequent underlines.

Furthermore, since there is no need to print an underline again when performing correction printing, printing ribbons can be saved and the time required to reprint the underline can also be saved.

(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, the main body frame 2 of the typewriter 1
A keyboard 3 is arranged in the front part of the printer, and a printing mechanism PM is arranged in the main body frame 2 behind the keyboard 3.
Further, a one-line liquid crystal display 75 for displaying input characters, symbols, etc. is provided at the rear of the keyboard 3.

The keyboard 3 is provided with character keys 10 including alphabet keys, numeric keys, and symbol keys, a space key 11, a collection key 12 for erasing printed characters, an auto underline key 13 for underlining, etc. There is. Note that the other keys have the same functions as those on 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 motor that drives it back and forth in the left and right direction, and its drive circuit, a type wheel 24 housed in a wheel cassette 23, a motor that drives it, its drive circuit, and a ribbon. The printing ribbon 26 stored in the cassette 25, the motor that winds it, its drive circuit, and the type 27 on the type wheel 24.
The printing hammer that hits the print hammer and the solenoid 28 that drives it.
A ribbon switching mechanism for selectively placing the printing ribbon or the correction ribbon 29 at the 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 will be explained based on the block diagram of FIG.

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

The control device C includes a main CPU 40 and its main CPU 4.
ROM (read/write) connected to 0 via a data bus etc.
RAM (Random Access Memory) 50 and RAM (Random Access Memory) 60.

The program memory 51 of the ROM 50 includes the keyboard 3.
A control program for controlling the printing mechanism PM and display mechanism in response to code data input from each character key and various function keys, a control program for character deletion to be described later, and the like are stored.

The RAM 60 includes a current position memory 61 that sequentially updates and stores the current position of the carriage 22 (print head) from the absolute origin in correspondence with the print position, as well as printed character data and attribute data such as underline and bold. and 2 bytes corresponding to the print position and approximately 50
Print data memory 62 that stores 0 characters and keyboard 3
an input buffer that stores data such as characters that are manually input from and displayed on the display 75; a cursor display position counter that counts according to the movement of the cursor in correspondence with each display position of the display 75; and data of the cursor display position counter. The cursor position that indicates the address of the input buffer corresponding to , and the underline mode flag 6 that is set when auto underline mode is set.
3, a print data pointer 64 for searching data at a designated address in the print data memory 62, and various memories for temporarily storing the results of calculations performed by the main CPU 40.

Based on the control program, the main CPU 40 causes the printing mechanism PM to print characters and symbols corresponding to the data input from each character key 10, and sequentially stores the print data in the print data memory 62 in correspondence with the print position. . Further, when the correction key 12 is operated, the print character 27 that is the same as the printed character is selected based on the data in the print data memory 62.
is struck three times via the correction ribbon 29 each time the carriage 22 moves by a minute amount, and the printed characters are erased.

The display mechanism includes an interface 70 and a display CPtJ.
71, a character generator 72, a display controller 73, and a liquid crystal display 75.
Connected as shown.

Approximately 400 types of dot matrix display data are stored in the character generator 72 in correspondence with code data in order to display characters and symbols on the display 75. The display CPU 71 reads out display data corresponding to command data and character data output from the main CPU 40 via the interface 70 from the character generator 72, and outputs the display data to the display controller 73. The display controller 73 stores the display data in the display RAM 74.
At the same time, a display signal corresponding to the display data is output to the display 75.

Next, the character erasing control performed by the control device C of the electronic typewriter will be explained based on the flowchart shown in FIG.

When the typewriter 1 is powered on, this control is started, and in step 31 (hereinafter simply referred to as Sl, and other steps are handled in the same way), initial settings such as resetting the underline mode flag 63 are executed. , move on to S2. In S2, the process waits for key human power, and if there is key human power, the process moves to S3. In S3, it is determined whether the input key is the character key 10 or the space key 11, and Y
If it is eS, it is determined in the next step 34 whether or not the auto underline mode is set, that is, whether or not the underline mode flag 63 is set. Then, when the auto underline mode is not set (when the auto underline flag 63 is reset), the process moves to S5. In S5,
Normal character printing without underlining corresponding to the input data is performed, and the process moves to S7.

If the automatic underline mode is set in S4, the process moves to S6, where characters corresponding to the input data are printed with an underline, and the process moves to S7.

In addition, in S6, when an underline has already been printed at the printing position, an underline stop control means is provided to prevent overlapping printing of the underline,
It is also possible to prevent overprinting of underlines (for details, see Japanese Patent Application No. 138625/1983). In S7,
The print data corresponding to the input key is stored in the print data memory 6.
2 is stored. If an underline is added in S6, the print data including the underline is stored in the print data memory 62, and the process returns to S2. For example, as shown in FIG. 5(a), steps S2 to S4 and S6 to S7 are repeated to print the character string rABCJ with an underline.

When the collection key 13 is operated, the process moves to S8 via S2 to S3. If it is determined Yes in S8, S
9, data at the address corresponding to the print head position in the print data memory 62 is read out based on the data in the current position memory 61. Then, in the next SIO, it is determined whether the data is character data (including underlined space data), and if it is character data, SIO
11.

In Sll, data in the current position memory 61 is written to the print data pointer 64, and first the print data pointer 64 is
The print data in the print data memory 62 that is obtained by subtracting 1 from the data in the print data memory 62 (the print data one position above the print head position) is read out, and then the print data in the print data memory 62 that is obtained by adding 2 to the print data pointer 64 ( (Print data one position below the print head position) is output one after another. In the next step 512, whether or not there is underline data in the print data before and after reading, that is, in the print data memory 62
It is determined whether the underline bit provided in the lower one byte of one character data is 1 or O, and if there is underline data, the process moves to S13. In this state, for example, as shown in FIG. 5(a), the print head is located at the printing position of the character "rB", and the printed character "A" is located one position above the print head position, and the character "A" is printed one position below the print head position. The printed characters “
"B" is underlined.

In S13, the print data excluding the underline data is erased 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, solenoid 28, correction ribbon 29, etc. of the printing mechanism PM are driven, and the erasing operation is performed while moving the carriage 22 by a minute amount left and right. Repeat multiple times to erase a given character. More specifically, first, the correction ribbon 29 is positioned at the printing position,
The same printed characters 27 as the characters to be erased are placed at the striking position. Then, operate the solenoid 28 to hit the type 27,
The printing ink is stripped off with a correction ribbon 29. Next, the carriage 22 is moved to the right by 0.2 mg+ (1/120 inch) and the same erasing operation as above is performed. Furthermore,
The carriage 22 is moved to the left by 0.4 am (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 m, the carriage 22 is returned to its original position, and the lifted correction ribbon 29 is lowered to complete the erasing process. (See No. 147376, 1983). For example, the fifth
As shown in the figure "bj," only the character rB is erased.

In the next step 314, in the print data memory 62,
The character code of the erased print data is erased, the space code is written, and the process returns to S2.

Then, when printing characters at the erased position, if the current auto underline mode is selected, S2 to S4 and S
After steps 6 to S7, the corrected characters are printed without printing an underline again. For example, as shown in FIG. 5(C), only the corrected character "C" is printed.

On the other hand, if the determination is No in Si2, the process moves to 315. For example, as shown in FIG. 6(a), the character string rA
Of BcJ, only the character rB is underlined, and the print head is located at the character rB position.

In S15, printed characters (including underlines) are 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 type wheel 24, solenoid 28, correction ribbon 29, etc. of the printing mechanism PM are driven, and the erasing operation is performed multiple times while moving the carriage 22 by a minute amount left and right. to the specified character (
(including underlines). The erase operation is S1
As in case 3, the erasing operation is performed three times with a slight change in position. When the erasing process is completed, the process moves 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. When printing characters at that position, if the underline mode is selected, select S.
After 2~S4 and S6~S7, corrected printing is done with underline, and if it is not underline mode, 32~
After steps S5 and S7, the corrected character "D" is printed as shown in FIG. 6(c).

If the SIO determines No, the process moves to 317, where it is determined whether the data is the first data in the print data memory 62. If it is the first data in the print data memory 62, character deletion is impossible, so the next step is In step 319, the alarm is processed and the process returns to S2.

Further, in step 317, if the print data is not the first data in the print data memory 62, the process moves to step 318. 3
At step 18, the carriage 22 is moved by one character in the pressure printing direction based on the data in the current position memory 61 and the data in the print data memory 62, and the process moves to S9. That is, S9
.about.310.S17 to 318 are repeated, and unless character erasure becomes impossible, the search is sequentially performed in the pressure printing direction until character data is detected. This makes it possible to automatically detect character data even if the print head is in a position after a tab or space operation.

Note that if a key other than the character key 10, space key 11, or collection key 12 is operated, the determination result of S8 will be N.
o, and in S20, a process corresponding to the operated key, such as setting or canceling the auto underline mode, is executed, and the process returns to S2.

As explained above, when at least one of the printed characters before and after the erased character (printed characters in one pressure printing direction and one printing direction) is underlined, only the erased character is erased and the underline is erased. Therefore, the underline is not interrupted, and continuous and beautiful underline printing can be performed.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram of the printing device of the present invention, and FIG.
FIG. 6 shows an embodiment of the printing device according to the present invention.
Fig. 2 is a perspective view of the typewriter, Fig. 3 is a block diagram of the control system of the typewriter, Fig. 4 is a flowchart of the control routine, Figs. 5 and 6 are diagrams showing the printing/erasing situation,
FIG. 7 is a diagram showing a conventional erasing situation. 3. Keyboard, 12. Collection key, 2
9... Correction ribbon, 40... Main CPU, 50...
ROM, 60...RAM, 61...Current position memory, 62...Print data memory, 63...Underline mode flag, C...Control device, PM...
・Printing mechanism. Patent applicant Brother Industries, Ltd. Figure 1 Figure 5 (CI) Ri (b) Anal (C) Day Figure 6 (a) AdanC (b) AC (□ ADC Figure 7 HEN -?-;

Claims (1)

[Claims] (1) A printing mechanism that prints on a print medium based on input data, a print data memory that stores this print data and underline information for the print data, and stores the current position of the print head of the printing mechanism. The printing mechanism is moved by a minute amount in accordance with the current position memory and the erase command signal,
In a character erasable printing device having an erasing mechanism that erases printed characters by operating at multiple positions, when an erasing command signal is received, the current position memory determines the upper and lower positions of the designated printing position. a judgment means for judging whether or not data is underlined; and according to the judgment means, when at least one of the printed data on both sides is underlined, even if the erased character is underlined, the judgment means determines whether the data is underlined or not. 1. An erasing control means for erasing only characters by the erasing mechanism without erasing characters.