PRINTER WITH ERASING FUNCTION

Abstract: A thermal transfer printer with an erasing function for recording data by use of heating energies comprises: a signal generator to generate a signal to instruct the erasure; a heating energy generator; a memory in which generation patterns of heating energies to be generated from the heating energy generator are stored; and a controller to control the heating energy generator in a manner such that a plurality of different generation patterns are read out of the memory on the basis of the erasing instruction from the signal generator and the different heating energies are generated from the heating energy generator a plurality of times on the basis of the generation patterns, thereby erasing recorded patterns. The heating energy generator gives the heating energies to the recorded patterns through a correctable ribbon (CR) which can print and erase. With this printer, the data recorded by variable lengths in the proportional spacing mode can be certainly erased.

Description: BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a printer with an erasing function and, more particularly, to a thermal printer with an erasing function in an apparatus for recording by the use of heating energies. Related Background Art Various kinds of printers with the erasing function have been proposed. Even among the thermal transfer printers for recording by use of heating energies, in recent years, the thermal transfer printer with the erasing function has been developed. However, it is the present situation that the erasure cannot always be performed with certainty. Further, in the case where the character data to be erased has been deleted from a buffer, the erasure span is not specified. Therefore, a method whereby the erasure is manually performed by an instruction of the operator is considered. In this case, the foregoing drawback causes a further large problem. U.S. patent specification 4545693 discloses a printer with an erasing function which can be performed by applying a heating energy onto an ink on a sheet through contact with the sheet. The arrangement includes a signal generator for generating a signal to instruct an erasure and heating energy generating means for generating heating energy together with memory means for storing therein generation patterns of heating energy to be generated by the heating energy generating means. SUMMARY OF THE INVENTION According to the present invention, a printer with an erasing function which can be performed by applying a heating energy onto an ink on a sheet through contact with the sheet, comprises: signal generating means for generating a signal to instruct an erasure; heating energy generating means for generating a heating energy; and memory means for storing therein generation patterns of heating energy to be generated by said heating energy generating means; characterised in that there are at least two generation patterns which complement one another and which correspond to recording timing for one dot and which have different complementary pulse widths, and in that said printer further comprises control means operative such that the complementary generation patterns are read out of said memory means in response to the signal from said signal generating means, and operative such that the heating energies are generated by said heating energy generating means by the complementary different pulse widths predetermined in succession on the basis of the complementary generation patterns, irrespective of recorded patterns to be erased, so that in use a character is erased in two stages by said at least two complementary patterns being applied in succession. According to the present invention, a method of erasing printing by applying a heating energy onto an ink on a sheet through contact with the sheet, comprises: generating a signal to instruct an erasure; generating a heating energy; and storing in a memory generation patterns of heating energy to be generated; characterised in that there are at least two generation patterns which complement one another and which correspond to recording timing for one dot and which are provided with different complementary pulse widths for controlling the read out of the generation patterns in response to the said signal such that the heating energies are generated by said complementary different pulse widths in succession on the basis of the complementary generation patterns, irrespective of the recorded patterns to be erased, the character being erased in two stages by the application of the two complementary patterns. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1A and 1B are explanatory diagrams of patterns for erasure according to the present invention; Fig. 2 is a flowchart for erasure (by a zigzag pattern); Fig. 3 is a flowchart for the MN control; and Fig. 4 is a flowchart for manual erasure. (Erasure control) - Figs 1A and 1B. Figs. 1A and 1B show examples of font patterns for erasure stored in a ROM. Practically speaking, each of these patterns consists of 24 x 8 dots and this pattern is repetitively used. For the pattern to be erased, if the ink which was all recorded by being heated by the M data is peeled off, there is a fear such that the heating energies are accumulated and the ribbon is stuck to the paper or a dirtying occurs. (MN control) Therefore, the N data obtained by reducing the heat pulse width of the M data to the interval of one dot in the lateral direction is heated. Further, since the erasing energy with respect to the first dot is low, by starting the heating from the timing which is preceding by two dots, the erasing energy of the first dot rises and this dot can with certainty be erased. This erasure can be accomplished by use of the pattern shown in Fig. 1A or 1B. (Double erasure by the opposite zig-zag patterns) Figs. 1A and 1B show the fonts of the zig-zag boxes which are used in the erasing mode. The dots are thinned out at intervals of one dot in each of the vertical and lateral directions. In this embodiment, the first erasing operation is executed in Fig. 1A. However, in order to be sure of erasing a character, it is necessary to erase again, i.e., twice. In the case of erasing at the second time, the font of Fig. 1B is used. The font of Fig. 1B is opposite or complementary to the font of Fig. 1A. The erasure is performed by shifting the M an N data positions by one dot at the second time as compared with the first erasing time. The order in which the fonts of Figs. 1A and 1B are used may be reversed. As explained above, the printed character can be erased with certainty by executing the erasing process twice by the use of the opposite or complimentary fonts. (Manual erasure) In the automatic erasing mode, the erasure span is determined by the width of the characters stored in the buffer. When the buffer is filled with characters, the characters are sequentially deleted from the buffer. When erasing the characters from the buffer, since the width data to be erased is not stored, the operating mode enters the manual erasing mode. In the manual erasing mode, this mode needs to be notified to the operator and the width of the character to be erased needs to be input by the key. The erasure span of the key-in character is obtained by the font and pitch (whole width and double width) which are being displayed at present. Thus, the character of only the erasure span obtained can be erased. Namely, the operator can freely select the erasure span and erase the character of the erasure span. (Flowchart for erasure (by the zig-zag patterns) - Fig. 2. The processing routine is started in step S1. In step S2, the MN dot pattern 1 is set. In this case, the dots and heat pattern in Fig. 1A are used. In step S3, the MN control (Fig. 3) is executed and the first erasure is performed. In step S4, the thermal head (carriage) which moved in association with the erasing operation is returned to the first erasure starting position. In step S5, the second MN dot pattern is set. In this case, the dots and heat pattern in Fig. 1B are used. In step S6 the MN control (Fig. 3 is executed and the second erasure is performed. The processing routine ends in step S7. In this embodiment, the heating energies can be also further changed in a plurality of erasing operations as mentioned above in the erasure. By sequentially reducing the heat pulse widths in accordance with the number of erasing operation times in consideration of the heat accumulation of the head, the heating energies can be held to a constant proper value every time. This method is particularly useful in the case of using the correction (CR) ribbon. (Flowchart for the MN control) - Fig. 3. In step S1, the control is started. In step S2, a width of character to be erased is obtained from the character generator (CG) and set into a character count unit in a RAM. In step S3, the character count value obtained in step S2 is increased by "2". Thus the erasure can be performed from the timing which is preceding the character by two dots. In step S4, the excitation phase of the stepping motor is switched. In step S5, a check is made to see if the character count value obtained in steps S2 and S3 is an even number or an odd number. If it is an odd number, step S9 follows. If it is an even number, the M data is obtained in step S6. In step S7, the heat pulse width of the M data is derived. In step S8, the M data obtained in steps S6 and S7 is heated. Then, step S12 follows. In step S9, the N data is obtained. In step S10, the heat pulse width of the N data is obtained. In step S11, the N data obtained in steps S9 and S10 is heated. Then, step S12 follows. In step S12, the character count value is decreased by "1". In step S13, a check is made to see if the character count value is "0" or not. If it is not "0", the processing routine is returned to step S4. If it is "0", the control ends in step S14. (Flowchart for manual erasure) - Fig. 4. In step S1, the processing routine is started. In step S2, a message is displayed by an LCD to inform the operator of the fact that the manual erasing mode has been set. In step S3, a check is made to see if the key input has been made or not. If NO, step S3 is repeated. If the key input has been made, a check is made in step S4 to see if it indicates the END key or not. If it is the END key, step S8 follows. If NO, a check is made in step S5 to see if the input key is the character key or not. If NO, the processing routine is returned to step S3. If it is the character key, a width of character corresponding to the input key is obtained from the CG to thereby obtain the erasure span in step S6. In step S7, the erasing operation is performed by only the amount of the erasure span obtained in step S6. Then, step S3 follows. In step S8, the message displayed on the LCD is cleared and the end of manual erasing mode is informed to the operator. The processing routine ends in step S9. Even if the ribbon was variably changed, the proper heat control can be always performed. Therefore, the printer which can perform the very high quality recording can be provided. Even in the heat cycles other than the heat cycle (recording timing) of the dot as the data to be recorded, by performing the preheat to record this dot, the very high quality recording can be performed. It is possible to provide a thermal transfer printer comprising: heating energy generating means for generating heating energies; means for transferring dot information to be recorded; and control means for controlling the heating energy generating means in a manner such that when recording the dot information transferred by the transferring means, after the first preheating energies were generated in the first recording cycle prior to the dot information to be recorded in the second recording cycle, the second preheating energies different from the first preheating energies are further generated before the heating energies corresponding to the dot information are generated in the second recording cycle. On the other hand, by uniforming the heating energies, the high quality recording can be performed. Even in the case of recording at a low speed, the very high quality recording can be executed. One dot in the left edge portion of a recording pattern, particularly, one independent dot in each of the upper and lower directions can be recorded with certainty. Even in the heat cycles other than one heat cycle of the dot information to be recorded, the preheat is given, and in a predetermined heat cycle, the heating energies corresponding to the dot information to be recorded are not generated, so that a very high quality underline can be recorded. Since the preheat is increased for the first dot of the underline, the underline can be recorded from the beginning at a high quality. By eliminating the heat pulses corresponding to the dot information to be recorded in predetermined cycles and by reducing the number of pulses within one heat cycle, the concentration of the heating energies can be prevented, so that the underline of a very quality can be recorded. Not only by reducing the heat pulse width but also by deleting the heat pulses within one heat cycle, the concentration of the heating energies can be prevented. Therefore, the heating energies can be independently applied to the characters and underline. Both of the characters and underline can be printed at a high quality. Even in the cycles other than one heat cycle of the dot information to be recorded, by applying the preheat and by eliminating the preheat in predetermined cycles, the underline of a very high quality can be recorded. Since the amount of preheat is increased for only the first dot of the underline, the underline can be recorded at a high quality from the beginning. By reducing the number of preheat pulses at intervals of one dot, the concentration of the heating energies can be prevented, so that the underline of a very high quality can be recorded. Due to this, not only by reducing the heat pulse width but also by eliminating the heat pulses within one heat cycle, the concentration of the heating energies can be prevented. Therefore, the heating energies can be independently applied to the characters and underline, so that both of the characters and underline can be printed at a high quality. In the case of recording "⊐"-, " "-, " "-, and "▭"- shape dot patterns consisting of at least the dots of the directions including the dots in the right direction, preheating to record the dots in the right direction is not performed, so that the high quality recording without deformation can be executed. In an apparatus for recording dot information by use of the heating energies, it is possible to provide a printer comprising: heating energy generating means for generating heating energies; reading means for reading out dot information indicative of a pattern to be recorded; and control means for controlling the heating energy generating means in a manner such that in the case where the pattern which was read out by the reading means is a pattern in which the dot information exists at least three peripheral directions including the dot information in the recording direction, the preheating energies to record the dot information in the recording direction are not generated. In the case of recording dot information surrounded by the dot information to be together recorded in four peripheral directions, the heating energies are reduced to a degree so as not to form a blank in the center with respect to that dot information, so that even in the case of "▭"- shape dot pattern, the high quality recording can be performed. In an apparatus for recording dot information by the use of heating energies, it is possible to provide a printer comprising: heating energy generating means for generating heating energies; reading means for reading out dot information indicative of a pattern to be recorded; and control means for controlling the heating energy generating means in a manner such that in the pattern which was read out by the reading means, in the case of recording the dot information in which the dot information exists in four peripheral directions, only the preheating energies to record the dot information in the recording direction are generated within the cycle to record the relevant dot information, or to provide a control method for such a printer. By correcting the heating energies for not only the first dot but also a few dots, it is possible to provide a thermal transfer printer which can perform the very high quality recording. By continuously correcting the heating energies, the recording can be executed with certainty even at the start of the recording at low temperatures or the like. In the recording cycle before the recording cycle of the dot information to be recorded, by applying additional preheating energies in the further upper or lower direction of the preheating energies to be applied, in particular, the independent dot information can be recorded with certainty.

Claims: A printer with an erasing function which can be performed by applying a heating energy onto an ink on a sheet through contact with the sheet, comprising: signal generating means for generating a signal to instruct an erasure; heating energy generating means for generating a heating energy; and memory means for storing therein generation patterns of heating energy to be generated by said heating energy generating means; characterised in that there are at least two generation patterns which complement one another and which correspond to recording timing for one dot and which have different complementary pulse widths (M,N), and in that said printer further comprises control means operative such that the complementary generation patterns are read out of said memory means in response to the signal from said signal generating means, and operative such that the heating energies are generated by said heating energy generating means by the complementary different pulse widths in succession on the basis of the complementary generation patterns, irrespective of recorded patterns to be erased, so that in use a character is erased in two stages by said at least two complementary patterns being applied in succession. A printer according to Claim 1, wherein said heating energy generating means gives the heating energies to the recorded patterns through a correctable ribbon which can print and erase. A printer according to Claim 1, further comprising a display means for displaying dot information to be recorded. A printer according to Claim 1, wherein said heating energy generating means comprises a thermal head which applies a heating energy onto the ink sheet. A printer according to Claim 1, wherein said memory means stores information as to the width of a character pattern to be output. A printer according to Claim 1, wherein said printer is capable of outputting information in mono-colour. A printer according to Claim 1, wherein said printer is capable of outputting information in multi-colour. A printer according to Claim 1, wherein said signal generating means comprises an erasure key. A printer according to Claim 1, wherein said memory means stores a plurality of kinds of patterns of heating energy. A method of erasing printing by applying a heating energy onto an ink on a sheet through contact with the sheet, comprising: generating a signal to instruct an erasure; generating a heating energy; and storing in a memory generation patterns of heating energy to be generated; characterised in that there are at least two generation patterns which complement one another and which correspond to recording timing for one dot and which are provided with different complementary pulse widths for controlling the read out of the generation patterns in response to the said signal such that the heating energies are generated by said complementary different pulse widths in succession on the basis of the complementary generation patterns, irrespective of the recorded patterns to be erased, the character being erased in two stages by the application of the two complementary patterns. A method according to Claim 10, wherein the heating energy is applied to the recorded patterns through a correctable ribbon which can print and erase. A method according to Claim 10, in which the dot information to be recorded is displayed. A method according to Claim 10, wherein the heat is provided by a thermal head which applies heating energy onto the ink sheet. A method according to Claim 10, wherein information as to the width of a character pattern to be output is stored in memory. A method according to Claim 10, wherein information in mono-colour is output. A method according to Claim 10, wherein information in multi-colour is output. A method according to Claim 10, wherein the signal is generated by an erasure key. A method according to Claim 10, wherein a plurality of kinds of patterns of heating energy is stored in memory.

Inventors: MIZOGUCHI, SHIGERU, OHSHIMA, NORIYOSHI, SHIBAMIYA, YOSHIKAZU, SUKIGARA, AKIHIKO, WADA, YUZO
Applicants: CANON KABUSHIKI KAISHA
Application year: 1987
Main classification: B41J2
IPC codes: B41J29