JPH0671812B2 - Character erasable printing device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a character erasable printing device, and in particular, when erasing an underlined character, based on the underline data of the printed characters before and after the erased character. The present invention relates to a character erasable printing device in which an underline is erased without moving a print head.

[Prior art]

Generally, 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 this autocorrection mechanism, there are a cover wrap method in which a correction agent is pasted on an erroneously printed character, and a lift-off method in which the printed ink is stripped off by 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, and the printing elements are required to be at the same position during printing and during erasing. That is, if the stop position of the printing element deviates even a little during printing and during erasing, a portion of the printed ink that cannot be stripped will occur. Therefore, in order to completely erase the erroneously printed character, it is required that the printing elements are completely at the same position during printing and during erasing.

However, obtaining the stop position accuracy of such a printing element has a mechanical and cost limit.

Therefore, conventionally, for example, JP-A-56-46992 and JP-A-60-1
In Japanese Patent Laid-Open No. 47376, in a printing apparatus adopting a lift-off method, a carriage is moved to the left and right by a small amount, and an erasing operation is performed a plurality of times so that the ink of the erroneously printed character is completely stripped off.

[Problems to be solved by the invention]

In the above-mentioned conventional printing apparatus, when the underlined character is printed by the autocorrection function when the underlined character is printed, the underline can be simultaneously deleted.

At this time, as described above, the printing device 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 a small amount in addition to the character width of the underline type.

Therefore, for example, as shown in FIG. 7, when the underlined print character is erased and the correction print is performed with the underline (for example, the letter “H”), the underline 80 corresponds to a minute movement amount of the carriage. Since there is a gap 81 between the underlines, the gaps are interrupted, and there is a problem that it is not possible to print clean underline that is continuous with the underlines before and after.

[Object of the Invention]

An object of the present invention is, when erasing an underlined character, based on the underline data of print characters before and after the erased character, when the underline data is continuous, the underline is erased without moving the print head. It is to provide a printing device capable of erasing characters.

[Means for solving problems]

As shown in the functional block diagram of FIG. 1, a character erasable printing device according to the present invention comprises input means for inputting data such as characters and symbols, a plurality of characters, a printing hammer and a printing ribbon. Printing means for printing characters or symbols corresponding to input data on a printing medium, print data memory for storing code data of printed characters or symbols and underline data in correspondence with printing positions, and printing by the printing means The current position memory that stores the current position of the head in correspondence with the print position, and the current position and its position based on the data in the print data memory and the data in the current position memory when an erase command is input from the input means. At the position where the print head is slightly moved back and forth, the type of the same letter or symbol as the letter or symbol to be erased is struck multiple times with a print hammer through the erase ribbon, In a character erasable printing device having erasing means for erasing the characters and symbols of the present invention, when erasing by the erasing means, based on the data of the current position memory, the current position of the print head from the print data memory and its upper one Retrieval means for retrieving underline data of the side print position and one lower print position, and underline data is detected by the search means at the current position of the print head and one of the upper print position or one lower print position. The underline at the current position is provided with an underline erasing control means for erasing by the erasing means without slightly moving the print head.

[Action]

In the character erasable printing device according to the present invention, the printing means having a plurality of characters, the print hammer and the print ribbon prints characters or symbols corresponding to the input data input from the input means on the print medium.

The code data of characters and symbols printed by the printing means and the underline data are stored in the print data memory corresponding to the printing position, and the current position of the print head of the printing means corresponds to the printing position and the current position memory. Memorized in.

When an erasing command is input from the input means, the erasing means causes the erasing means to erase the character or symbol corresponding to the current position of the print head based on the data in the print data memory and the data in the current position memory. Characters that are the same as the characters or symbols to be erased at the position where the print head is moved slightly back and forth are erased by hitting multiple times with a print hammer through the erase ribbon.

When erasing the print characters by the erasing means, the searching means detects, from the print data memory, the underline data of the print head and one upper side printing position and one lower side printing position based on the data of the current position memory. To do. When the retrieving means detects underline data at the current position of the print head and one of the upper print position or the one lower print position, the underline erasing control means causes the erasing means to slightly move the print head. Without deleting the underline at the current position.

〔The invention's effect〕

As described above, according to the character erasable printing device of the present invention, when erasing a character or a symbol, the current position of the print head and one of the upper print position or the one lower print position thereof are set. When underline data is detected,
Since the underline at the current position is erased without slightly moving the print head, the underline is erased by the character width of the underline type.

That is, if you correct and print with underline after erasing characters,
There is no gap between the underline and the underline at the one upper print position or the one lower print position, and there is no discontinuity, and continuous and clean underline printing can be performed.

〔Example〕

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

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

As shown in FIG. 2, a keyboard 3 is arranged at the front of the body frame 2 of the electronic typewriter 1, and a printing mechanism PM is arranged at the body frame 2 behind the keyboard 3.
In addition, a liquid crystal display 75 for one line is provided at the rear of the keyboard 3 for displaying characters and symbols that have been input.

The keyboard 3 includes a character key 10 including alphabetic keys, numeral keys and symbol keys, a space key 11, an erase key 12 for erasing print characters, an auto-underline key 13 for underlining, and various function keys. It is provided like 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 printing 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 of the type, the solenoid 28 for driving it, its drive circuit, the ribbon switching mechanism for selectively arranging the printing ribbon 26 or the correction ribbon 29 at the printing position, and the like are provided.
Is similar to the printing mechanism of an ordinary 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 electronic typewriter 1 is basically composed of a keyboard 3, a printing mechanism PM, a display mechanism D, a control device C and the like, and the keyboard 3, the printing mechanism PM and the display mechanism D are main parts of the control device C via a data bus or the like. It is connected to a CPU (Central Processing Unit) 39.

The control device C is composed of a main CPU 39, a ROM (read only memory) 40 and a RAM (random access memory) 50 connected to the main CPU 39 via a data bus or the like.

In the program memory 41 of the ROM 40, a control program for controlling the printing mechanism PM and the display mechanism D corresponding to code data input from each character key or various function keys of the keyboard 3 and an underlined character erasing control which will be described later. A control program 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 association with the print position, code data such as printed characters, underline, bold, etc. Approximately 50 in sequence with 2 bytes corresponding to the attribute data and the print position.
A print data memory 52 for storing 0 characters, an input buffer for storing data such as characters input from the keyboard 3 and displayed on the display 75, a text memory for storing the input data as file data, and a cursor display position are displayed. A cursor display position counter that counts according to the movement of the cursor in correspondence with each display position of 75, a cursor position pointer that indicates the address of the input buffer corresponding to the data of the cursor display position counter, and an instruction in the print data memory 52 Print data pointer 53 to search the data of the specified address, and the main CPU3
Various memories are provided for temporarily storing the results of arithmetic processing in 9.

Main CPU39, each character key 1 based on the control program
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 52 in correspondence with the print position.

Further, when the delete key 12 is operated, the main CPU 39 strikes the print mechanism PM via the correction ribbon 29 with the same type 27 as the print character based on the data of the current position memory 51 and the data of the print data memory 52. Let it erase. In this case, the print head is struck once at the current position, then the print head is struck once at a position slightly moved in the printing direction by, for example, 1/240 inch, and then the print head is moved in the opposite printing direction from the current position. It is struck once at a position slightly moved by 1/240 inch, and erased by a total of three hits.

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.

The display CPU 71 is the main CPU via the interface 70.
Based on the command data and character data output from 39,
Display data corresponding to these is generated by the character generator.
It reads from 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. Further, the display CPU 71 also performs cursor movement control for instructing the display controller 73 of the address of the cursor movement destination according to the cursor movement data from the main CPU 39 via the interface 70.

Next, the underlined 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 the process proceeds to step S1 (hereinafter referred to simply as S1 and other steps are handled in the same manner) to execute the initial setting, and wait for key input in S2. . When a key is input, the process proceeds to S3, and it is determined whether or not the erase key 12 is present. If the erase key 12 is not present, for example, if it is the character key 10, the process proceeds to S4 and the input data is printed and the print data is stored in the print data memory. It is stored in 52 and returns to S2. At this time, the main CPU39 is the printing mechanism PM.
And outputs a control signal to each drive circuit.

When the delete key 12 is operated, it is determined as Yes in S3 and the process proceeds to S5. In S5, the data of the current position memory 51 is written in the print data pointer 53, and the data of the address corresponding to the print head position of the print data memory 52 is read based on the data of the print data pointer 53. Then, in the next S6, it is determined whether or not the data is print data, and when it is print data, the process proceeds to S7.

In S7, it is determined whether there is underline data, that is, whether the underline addition bit provided in the lower 1 byte of the read data is "1". If there is underline data, Move to S8. In S8, 1 is subtracted from the print data pointer 53, and based on this data, the print data corresponding to the print position in the print data memory 52 in the direction opposite to the print head by one character is read out.

In S9, it is determined whether there is underline data, that is, whether the underline is continuous,
If there is underlined data, the process proceeds to S10. For example, as shown in FIG. 5 (a), the print head is located at the print character of the character "B", and the characters "A" and "B" are continuously underlined. .

In S10, the print characters except the underline are erased. For example, as shown in FIG. 5B, the character "B" excluding the underline is based on the normal erasing process, that is, the character code of the character "B". The correction ribbon 29 or the like is driven, and the carriage 22 is moved to the right or left by a small amount, and the erasing operation is executed three times to erase the character "B".

In S11, the underline is erased without moving the print head. For example, as shown in FIG. 5 (c), the underlined type 27 is struck through the correction ribbon 29 one or more times to erase the underline when the print head is located at the print position. . That is, the underline is erased by the length corresponding to one character.

In S12, the space code is written in the address of the print data memory 52 corresponding to the erased data, and the underlined data is removed and erased, but the data is erased from the print data memory 52, and the process returns to S2.

Then, when the character key 10 is operated in the automatic underline mode for correction printing, the character corresponding to the character key 10 is printed with an underline in S4 through S2 to S3.
For example, as shown in FIG. 5 (d), the character "D" is printed with underlining. At this time, the underline is continuously printed without interruption.

On the other hand, if No is determined in S9, the process proceeds to S13. At S13,
1 is added to the print data pointer 53, and the print data corresponding to the print position of the print head position in the print data memory 52 in the one-character print direction is read based on this data. Then, in S14, it is determined whether there is underline data, that is, whether the underline is continuous, and if there is underline data,
The process moves to S10, the print characters except the underline are erased, then the underline is erased in S11, and then S12.
The data erased at is erased from the print data memory 52, and the process returns to S2. For example, as shown in FIG. 5 (a), the print head is located at the print position of the character "B", and the characters "B" and "C" are continuously underlined. Sometimes, the character "B" is erased first, and then the underline is erased by the length corresponding to one character (see FIGS. 5B and 5C).

Also, when it is determined No in S7 or No in S14, that is, when the underline is not continuous, the process proceeds to S15, and the print character corresponding to the print head position is (with an underline). It is erased (sometimes with an underline), the data is erased from the print data memory 52 in the next S12, and the process returns to S2. For example, as shown in FIG. 6 (a), the print head is located at the printing position of the character “B”, and when the underline is printed only on the character “B”, FIG. 6 (b). As shown in
The character "B" and the underline are normally erased, that is, based on the character code of the character "B" and the underline addition bit, the type wheel 24, solenoid 28, correction ribbon 29, etc. of the printing mechanism PM are driven. The carriage 22 is moved to the left and right by a small amount, and the erasing operation is performed three times each to erase the character "B" and the underline, and also erase from the print data memory 52.

When it is determined No in S6, for example, when it is a space code, the process proceeds to S16, and the print head moves 1 in the reverse printing direction.
It is moved by the character. In next S17, print data pointer 5
The data of the current position memory 51 is written in 3, and the data of the address corresponding to the print head position of the print data memory 52 is read based on the data of the print data pointer 53. Then, in the next S18, it is determined whether or not there is print data, and if there is print data, S7 and subsequent steps are repeated, and if there is no print data, for example, if it is the first data in the print data memory 52, then the process proceeds to S19. , Alarm processing such as sounding the buzzer is performed, and the process returns to S2.

As described above, when erasing a character, when an underline is continuously printed on the print character to be erased and one print character on the print direction side or one print character on the opposite print direction side, , Since the printed character is erased surely through the slight movement of the print head first and the underline is erased without moving the print head next, the underline is the length corresponding to the character width of the underline type. It will only be erased.

That is, when the underlined character is corrected and printed, 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 for explaining the configuration of the present invention, and FIG.
1 to 6 show an embodiment of the present invention. FIG. 2 is a perspective view of an electronic typewriter, FIG. 3 is a block diagram of a control system of the typewriter, and FIG. 4 is an underlined character erasing control. FIG. 5, FIG. 6 and FIG. 6 are flowcharts for explaining the erase control of underlined characters, and FIG. 7 is a diagram for explaining the conventional erase control of underlined characters. 3 ... Keyboard, 12 ... Delete key, 13 ... Auto underline key, 26 ... Print ribbon, 27 ... Type, 28 ...
… Solenoid, 29 …… Correction ribbon, 39 …… Main CPU, 4
0 …… ROM, 50 …… RAM, 51 …… Current position memory, 52 ……
Print data memory, 53 …… Print data pointer, C ……
Control device.

Claims (1)

[Claims] 1. A printing means for printing characters or symbols corresponding to input data on a print medium, comprising: an input means for inputting data of characters or symbols; a plurality of characters; a printing hammer; and a printing ribbon. A print data memory for storing the code data of the characters and symbols and the underline data corresponding to the print position, a current position memory for storing the current position of the print head of the printing means in correspondence with the print position, and an input When an erase command is input from the means, based on the data in the print data memory and the data in the current position memory,
At the current position and a position where the print head is moved slightly before and after it, the type of the same character or symbol as the character or symbol to be erased is struck multiple times with a print hammer through the erase ribbon, In a character erasable printing device including erasing means for erasing a symbol, when erasing by the erasing means, the current position of the print head and one upper side printing from the print data memory based on the data of the current position memory are printed. Search means for searching the position and the underline data of the one lower print position, and the underline data is detected by the search means at the current position of the print head and one upper print position or one lower print position thereof. The underline at the current position is provided with underline erasing control means for erasing by the erasing means without slightly moving the print head. Character erasable printing apparatus according to claim.