JPS63260474A - Character-erasable printer - Google Patents

Abstract

PURPOSE:To erase the character width of an underlined type by detecting underline data at the present position of a print head, a printing position disposed at the upper or lower position by one, and erasing the underline of the present position without finely moving the head. CONSTITUTION:A main CPU 39 prints a character/symbol corresponding to data input from each character key 10 by a printing mechanism PM on the basis of a control program, and sequentially stores printing data corresponding to printing positions in a printing data memory 52. Further, when an erasure key 12 is operated, the CPU 39 hits the same type 27 as a printing character through a correction ribbon 29 by the mechanism PM on the basis of the data of a present position memory 51 and the data of the memory 52 to erase it. In this case, the erasure is executed by striking totally three times by first striking at the present position of a printing head, then striking the head at a position finely moved, for example, 1/240 inch in a printing direction, and eventually striking the head by finely moving it, for example, 1/240 inch from the present position in a reverse printing direction.

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 data of printed characters before and after the erased character. The present invention relates to a printing device capable of erasing characters, which erases underlines without moving the print head.

[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 types of auto-correction mechanisms: a cover wrap method in which a correction agent is pasted on the erroneously printed characters, and a lift-off method in which the printed ink is peeled off 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 stopping position of the printing element during printing and erasing is even slightly shifted, a portion of the printed ink will not be peeled off. Therefore, in order to completely erase erroneously printed characters, it is required that the printing element be in the completely same position during printing and erasing.

However, there are mechanical and cost limitations in achieving such precision in the stopping position of the printing element.

Therefore, conventionally, for example, in JP-A-56-46992 and JP-A-60-147376, in a printing device that employs a lift-off method, the carriage is moved by a minute amount left and right and the erasing operation is performed multiple times. , 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 minute amount left and right to erase the incorrectly printed characters, and also moves the carriage a minute amount left and right when erasing the underline, so the incorrectly printed characters are removed. Although the underline can be completely erased, in addition to the character width of the underlined type, the amount of minute movement will be erased.

For this purpose, for example, as shown in Figure 7, after erasing the underlined printed characters, the corrected characters are printed with the underline (
For example, when printing the letter "H"), the underline 80 is interrupted by a gap 81 corresponding to the small amount of movement of the carriage, so there is a problem that it is not possible to print a continuous and beautiful underline with the previous and subsequent underlines. be.

[Purpose of the invention]

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

[Means for solving problems]

As shown in the functional block diagram of FIG. 1, the character-erasable printing device according to the present invention includes an input means for inputting data such as characters and symbols, a plurality of characters, a printing hammer, and a printing ribbon. A printing means for printing characters and symbols corresponding to input data on a printing medium, a printing data memory for storing code data and underline data of the printed characters and symbols in correspondence with printing positions, and a printing means for printing. A current position memory stores the current position of the head in correspondence with the print position, and when an erase command is input from the input means, the current position and its current position are stored based on the data in the print data memory and the data in the current position memory. By slightly moving the print head back and forth, the printed characters or symbols that are the same as those to be erased are struck multiple times with a printing hammer through the erasing ribbon, thereby erasing the characters or symbols. In a printing device capable of erasing characters, which is equipped with an erasing means, when erasing is performed by the erasing means, the current position of the print head, one higher printing position, and one lower printing position are stored in the print data memory based on the data in the current position memory. a search means for searching for underline data at a side print position; Underline erasing control means is provided to cause the erasing means to erase the underline at the position without slightly moving the print head.

[Effect]

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

The code data and underline data of characters and symbols printed by the printing means are stored in the print data memory in correspondence with the printing position, and the current position of the print head of the printing means is stored in the current position memory in correspondence with the printing position. is memorized.

When an erasing command is input from the input means, the characters and symbols corresponding to the current position of the print head are erased by the erasing means based on the data in the print data memory and the data in the current position memory. The printed characters or symbols identical to those to be erased are erased by striking them multiple times with a printing hammer through an erasing ribbon at a position where the print head is slightly moved back and forth.

When erasing a printed character by the erasing means, the search means detects the underline data of the print head and its one higher printing position and one lower printing position from the print data memory based on the data in the current position memory. do. When the search means detects underline data at the current position of the print head and one print position above or below the current position, the underline erasure control means causes the erasure means to slightly move the print head. Erases the underline at the current position without moving.

〔Effect of the invention〕

As explained above, according to the character-erasable printing device according to the present invention, when erasing characters or symbols, the current position of the print head and one print position above or below the current position of the print head can be erased. When underline data is detected, the underline at the current position is erased without making a slight movement of the print head, so the underline is erased by the character width of the underlined type.

In other words, if you print the corrected text with an underline after erasing the characters,
There is no gap between the underline and the underline at the next higher printing position or the next lower printing position, so that continuous and beautiful underline printing is possible.

〔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 for displaying input characters, symbols, etc. is provided at the rear of the screen.

The keyboard 3 includes character keys 10 including alphabet keys, numeric keys, and symbol keys, a space key 11, an erase key 12 for erasing printed characters, an auto underline key 13 for underlining, and various function keys. It is set up like 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.
and its driving circuit, printing ribbon 26 or correction ribbon 29
A ribbon switching mechanism for selectively arranging the ribbon at a printing position is provided, and this printing mechanism PM 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 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 response to code data input from each character key and various function keys, and a control program for underlined character deletion control, which will be described later, 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 code data such as printed characters, underlines, bold, etc. a print data memory 52 that stores approximately 500 characters in 2-byte correspondence with attribute data of the print position, and an input buffer that stores data such as characters input from the keyboard 3 and displayed on the display 75. , a text memory that stores 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; Print data pointer 5 that searches data at a specified address in data memory 52
3, and various types of memories for temporarily storing the results of calculations performed by the main CPU 39.

Based on the control program, the main CPU 39 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 52 in correspondence with the print position. .

Furthermore, when the erase key 12 is operated, the main CPU 39
is the data of the current position memory 51 and the print data memory 5.
Based on the data of No. 2, printed characters 27 identical to the printed characters are struck by the printing mechanism PM via the correction ribbon 29 and erased. In this case, the print head is struck once at its current position, then struck once at a position where the print head is slightly moved, for example, 1/240 inches in the printing direction, and then the print head is moved from the current position in the counter-printing direction. Erasing is performed by striking once at a position slightly moved by 1/240 inch, for a total of three strikes.

The display mechanism includes an interface 70 and a display CPU 7.
1, a character generator 72, a display controller 73, and a liquid crystal display 75, which are connected as shown.

Approximately 400 types of dot matrix display data are stored in the character generator 72 in correspondence with the 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 39 via the interface 70 from the character generator 72, and outputs the display data to the display controller 73. The display controller 73 writes display data into the display RAM 74 and at the same time outputs a display signal corresponding to the display data to the display 75. Furthermore, the display CPU 71
In response to cursor movement data from the main CPU 39 via the interface 70, cursor movement control is also performed to instruct the display controller 73 about the address to which the cursor should be moved.

Next, the underlined character deletion 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 starts, moves to step SL (hereinafter simply referred to as SL, and other steps are handled in the same way), executes initial settings, and waits for key input in S2. .

When a key is input, the process moves to 83, and it is determined whether or not the erase key 12 is pressed.If it is not the erase key 12, for example, the character key 1
When the value is 0, the process moves to S4, where the input data is printed and the print data is stored in the print data memory 52.
Return to 2. At this time, the main CPU 39 controls the printing mechanism PM.
A control signal is output to each drive circuit.

When the erase key 12 is operated, a YES determination is made at 33, and the process moves to S5. In S5, the data of the current position memory 51 is written into the print data pointer 53, and based on the data of the print data pointer 53, the data of the address corresponding to the print head position of the print data memory 52 is read. Then, in the next step S6, it is determined whether the data is print data or not, and if it is print data, the process moves to S7.

In S7, it is determined whether there is underline data, that is, whether the underline addition bit provided in the lower one byte of the read data is "1", and if there is underline data, Move to S8.

At S8, 1 is subtracted from the print data pointer 53,
Based on this data, print data corresponding to a print position one character in the opposite print direction from the print head position in the print data memory 52 is read out.

In S9, whether there is underlined data or not,
That is, it is determined whether the underlines are continuous or not, and if there is underline data, the process moves to SIO. For example, as shown in FIG. 5(a), the print head is located at the printing position of the character r13J, and the character "A" is printed.
and the letter "B" are consecutively underlined.

In SIO, printed characters except underlines are erased. For example, as shown in FIG. 5(b), the character r13J excluding the underline is erased by the printing mechanism P based on the character code of the character r13J.
M type wheel 24, solenoid 28, correction ribbon 2
9 or the like to move the carriage 22 by a minute amount to the left or right and execute the erasing operation three times to erase the character "B".

At 311, the underline is erased without moving the printhead. For example, as shown in FIG. 5(c),
With the print head in the printing position, the underlined type 27 is struck one or more times via the correction ribbon 29 to erase the underline. That is,
The underline is deleted by a length corresponding to one character.

At 312, a space code is written to the address of the print data memory 52 corresponding to the erased data, and the underline data is removed and the erased 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 auto underline mode for correction printing, the steps 32 to S3 are followed by S4.
The character corresponding to character key 10 is printed with an underline. For example, as shown in FIG. 5(d), the character rp
J is printed with an underline. At this time, the underline is printed continuously without interruption.

On the other hand, if the determination is No in S9, the process moves to 313. 3
At step 13, 1 is added to the print data pointer 53, and based on this data, the print data corresponding to the print position in the print head position in the print direction of one character in the print data memo IJ52 is read out.

Then, in step 314, it is determined whether there is underline data, that is, whether the underlines are continuous, and if there is underline data, S
10, the printed characters except the underline are erased, then the underline is erased in Sll, then the erased data is erased from the print data memory 52 in 312, and the process returns to S2. For example, as shown in FIG. 5(a), the print head is located at the printing position of the character r13J, and when the underline is printed consecutively on the character rBJ and the character "C", The character "B" is erased, and then the underline is erased by a length corresponding to one character (see FIGS. 5(b) and 5(c)).

Further, when it is determined No in S7 or No in S14, that is, when the underlines are not continuous, the process moves to S15, and the print character corresponding to the print head position is (underlined). In the next step 312, the data is deleted from the print data memory 52, 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 letter "B". When the underline is printed only on the letter "B", as shown in FIG. b
), the character "B" and the underline are erased by the normal erasing process, that is, based on the character code of the character "rB" and the underline addition bit, the character "B" and the underline are erased by the type wheel 24, solenoid 28, and correction ribbon 29 of the printing mechanism PM. The character "B" and the underline are erased from the print data memory 52 as well as the character "B" is erased by driving the carriage 22 to move the carriage 22 by a minute amount left and right and carrying out three erasing operations at the same time.

When it is determined No in S6, for example, if it is a space code, the process moves to 516, and the print head is moved by one character in the opposite printing direction. In the next step S17, the data of the current position memory 51 is written to the print data pointer 53, and based on the data of this print data pointer 53, the data of the address corresponding to the print head position of the print data memory 52 is read out. . Then, in the next step 318, 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, when the first data of the print data memory 52 is S
19, an alarm process such as sounding a buzzer is performed, and the process returns to S2.

As explained above, when erasing characters, if an underline is printed continuously on the printed character to be erased and the printed character one character in the printing direction, or the printed character one character in the opposite printing direction, , the printed characters are first erased reliably through minute movements of the print head, and then the underline is erased without moving the print head, so the underline has a length corresponding to the character width of the underline type. It will just be erased.

In other words, when an underlined character is corrected and printed, the underline is not interrupted, and continuous and beautiful underline printing can be performed.

[Brief explanation of drawings]

Fig. 1 is a functional block diagram explaining the present invention in detail;
Fig. 6 shows an embodiment of the present invention, Fig. 2 is a perspective view of an electronic typewriter, Fig. 3 is a block diagram of the control system of the typewriter, and Fig. 4 is an underlined character erasing control. FIGS. 5 and 6 are diagrams illustrating erasure control of underlined characters, and FIG. 7 is a diagram illustrating conventional erasure control of underlined characters. 3. Keyboard, 12. Erase key, 13.
・Auto underline key, 26...Print ribbon,
27...Print, 28...Solenoid, 29...
Correction ribbon, 39...Main CPU. 40...ROM, 50...RAM, 51...Current position memory, 52...Print data memory, 53...
Print data pointer, C...control device. Patent applicant Brother Industries, Ltd. Figure 1 Figure 5 (a) ri (b) ■ (C) Δg (d) Day Figure 6 (a) AdanC (b) AC (C) ADC No. 7 FigureHEN-2-F

Claims (1)

[Claims] (1) An input means for inputting character and symbol data, etc., a printing means for printing characters and symbols corresponding to the input data on a print medium, which includes a plurality of type characters, a printing hammer, and a printing ribbon; A print data memory stores character and symbol code data and underline data in correspondence with the print position; a current position memory stores the current position of the print head of the printing means in correspondence with the print position; and an input means. When the erase command is input, 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 slightly moved before and after the current position, the characters or symbols that are the same as those to be erased are struck multiple times with a printing hammer through the erasing ribbon. In a character-erasable printing device equipped with an erasing means for erasing a symbol, when erasing is performed by the erasing means, the current position of the print head and the next higher printing character are retrieved from the print data memory based on data in the current position memory. a search means for searching for underline data at a position and one print position below the current position of the print head and underline data at one print position above or below the current position of the print head; 2. A printing device capable of erasing characters, characterized in that said character erasing control means is provided for causing an erasing means to erase the underline at the current position without slightly moving the print head.