JPS628317B2 - - Google Patents

Description

[Detailed description of the invention] Technical field The present invention relates to a dot matrix printer.

Conventional technology Conventionally, in dot matrix printers that print characters in dot matrix format, characters are printed with a uniform printing pitch (pica pitch, elite pitch, etc.) that is set regardless of the width of the character. However, when characters with different widths are successively printed, the blank spaces between the characters become uneven, resulting in a poor impression of the printed characters.

In order to solve the above drawbacks, in addition to the above-mentioned printing mode with a uniform printing pitch, a dot pattern common to each character, for example, a 5 x 7 dot matrix format consisting of a fixed dot pitch, corresponding to the width of each character is used. A format that has a printing mode that prints characters with a variable printing pitch that changes only the printing pitch, or a printing mode that prints with a dot pattern unique to each character and a variable printing pitch that corresponds to the width of each character with the dot pitch. Various types of dot printers have been proposed.

However, in the case of the former, characters are printed with a uniform width, so if the width is wide, for example "M"
In the case of letters such as "W", the width appears narrower than other letters, resulting in a bad impression of the printed letters.

In the latter case, in addition to character dot patterns with uniform printing pitch and data related to dot pitch, it is necessary to store character dot patterns with variable printing pitch and data related to dot pitch, which requires a large amount of memory. This has the drawback of increasing the cost of the dot matrix printer itself.

Purpose In view of the above-mentioned conventional drawbacks, the object of the present invention is to commonly use the dot pattern of characters with a uniform printing pitch and data regarding the dot pitch, and to print characters with a width corresponding to each character and with a variable printing pitch. An object of the present invention is to provide a dot matrix printer capable of printing.

Example The present invention will be described below with reference to Examples.

FIG. 1 is an electrical block diagram of a dot matrix printer according to the present invention. FIG. 2 is a time chart showing an example of printing in the first printing mode. FIG. 3 is a time chart showing an example of printing in the second printing mode. In the figure, the keyboard 1 has a large number of keys 2 corresponding to each character, a first printing mode MOD 1 that prints all characters at a uniform printing pitch, and a variable printing pitch that corresponds to each character. A changeover switch 3 is provided for selecting a second printing mode MOD2 to be printed using the switch 3. mode
A selection signal SES corresponding to MOD1 and MOD2 is output to the control circuit 4.

The memory 5 stores first timing data DT 1 that corresponds to the first printing character mode MOD1 and determines the printing timing from the beginning of the printing pitch of each character to the dot pattern printing start position of that character, which is common to each character _. , as well as second timing data DT ₂ for determining the dot pitch of each character,
When the first printing mode is MOD1, the dot pattern data DPD is commonly used for all characters, and the dot pattern data DPD is stored in each memory location corresponding to each character.
and first timing data DT ₁ which corresponds to the second printing mode MOD2 and determines the printing timing from the beginning of the character pitch unique to each character to the dot pattern printing start position of the character, and Second timing data _DT2 determining the unique dot pitch are stored.

First, switch 3 selects the first printing mode.
When key 2 is pressed after MOD 1 is selected, control circuit 4 outputs a code signal corresponding to key 2.
An address signal is sent to the memory 5 in response to CS and a selection signal SES corresponding to the first printing mode MOD1.
AS is output, and the dot pattern data DPD is accessed from the memory location of the character corresponding to key 2, and the first and second timing data DT ₁ and DT ₂ are accessed from the memory location corresponding to the first print mode MOD1. For example, a drive signal DS is output to a carriage drive member 6 consisting of a pulse motor, etc., and a carriage 8 on which a print head 7 having a large number of print wires (not shown) is placed and fixed is moved to a printing paper (not shown). 2) at a constant speed along the printed line.

The carriage 8 determines the first timing data DT ₁ based on a detection signal output from a timing fence in which a large number of slits are formed, for example, and a detector 9 which is arranged on the carriage 8 and is made up of a photodiode or the like. When the dot pattern printing start position is reached, which is a distance lo ₁ common to each character from the beginning of the printing pitch to be printed, the control circuit 4
outputs a print signal PS to the print head 7 in accordance with the accessed dot pattern data DPD, and selectively drives the print wire to print the first row of dots.

After the above operation, based on the detection signal, the carriage 8 moves from the first column determined by the second timing data DT ₂ to the second column separated by a distance l ₁ as a dot pitch common to each character. , similarly to the above, the control circuit 4 receives the dot pattern data.
After outputting the print signal PS to the print head 7 according to the DPD and printing the second row of dots, the carriage 8 is sequentially moved a distance l ₁ determined by the second timing data DT ₂ to print the dots. , prints characters in dot matrix format.

After the above operation, the carriage 8 is moved a distance lo ₁ determined by the first timing data DT ₁ ,
It is positioned at the beginning of the printing pitch of the next character to be printed, and by repeating the above operation, the character is printed at a uniform printing pitch based on the first and second timing data DT ₁ and DT ₂ common to each character. Ru.

Next, switch 3 selects the second printing mode.
When key 2 is pressed after MOD ₂ is selected,
The control circuit 4 similarly sends an address signal AS to the memory 5.
is output and the dot pattern data DPD and the first and second
At the same time, the carriage 8 is moved at a constant speed, and based on _the detection signal, the carriage 8 prints from the _beginning of the printing pitch determined by the first timing data DT ₁ to the character. When reaching the dot pattern printing start position separated by a specific distance lo ₂ , the printing signal PS is outputted according to the dot pattern data DPD to print the first row of dots, and the carriage 8 is then moved to the first position based on the detection signal. The dots are sequentially moved from the first column determined by the timing data DT ₂ of 2 to the second column and beyond, which are separated by a distance l ₂ as a dot pitch unique to each character, and the print signal PS is similarly output, and the dot pattern data After printing dots in each row according to the DPD and printing the letter "M" corresponding to the key 2 in dot matrix format, the carriage 8 is moved a distance lo ₂ determined by the first timing signal DT ₁ . Position it at the beginning of the print pitch of the next character to be printed.

Similar to the above operation, the carriage 8 is moved a distance lo ₃ , lo ₄ determined by the first timing data DT ₁ unique to the character, and printing starts when it is located in the first column. dots are printed sequentially at distances l ₃ and l ₄ determined by second timing data DT ₂ specific to do.

Therefore, in this embodiment, the width can be changed to a unique width corresponding to each character, and the variable printing pitch can be used to print at a character pitch unique to each character.
It can improve the impression of printed characters.

Furthermore, when printing characters in the second printing mode, the character dot pattern data DPD in the first printing mode MOD ₁ can be shared, so the above effect can be achieved using a small memory capacity, and the dot pattern data can also be It is possible to prevent the cost increase of matrix printers.

Although this embodiment has a closed-loop control configuration in which the amount of movement of the carriage 8 is detected based on the detection signal and the printing timing is determined, the present invention has an internal control system as shown in FIGS. 4A and 4B. The position where predetermined time t ₁ , t ₂ , t ₃ determined by the first timing data DT ₁ unique to each character has elapsed from the timings to ₁ and to ₃ of the detection signal by the timer 4a is set as the dot pattern printing start position. After printing the first row of dots, each dot is printed at the dot pitch at a predetermined time tm, ti, tc determined by the second timing data _DT2 unique to each character, and then the second row of dots is printed.
It is also possible to implement an open-loop control type configuration in which each character is printed in dot matrix format according to print mode MOD ₂ .

Furthermore, if the step motor that drives the carriage 8 is subjected to open-loop control, the oscillator clock signal, which is the reference signal for the excitation phase switching timing, is used as the reference signal for the first and second timing data. It can be implemented even if it is a configuration.

Further, although this embodiment has been described using a dot pattern in a 5x7 dot matrix format, the present invention can be implemented with any dot pattern in a 7x9 dot matrix format, a 24x24 dot matrix format, etc. .

Furthermore, although this embodiment has been described using an impact type dot matrix printer using a printing wire, the present invention can also be practiced with a dot matrix type thermal printer.

Effects As explained above, the dot matrix printer of the present invention not only stores the dot pattern of each character, but also stores the first dot matrix printer that determines the printing timing from the beginning of the print pitch of each character to the dot pattern printing start position of that character. Timing data and second timing data that determines the dot pitch of each character are stored as data common to each character for a first printing mode, and unique data for each character is stored for a second printing mode. A memory is provided for storing each character in a memory location corresponding to each character, and in the first printing mode, all the characters are printed using the common first and second timing data, and in the second printing mode, In this case, by using a configuration that allows the dot pattern to be shared in both the first and second printing modes, which are unique to each character, it is possible to use a small memory capacity to print with a width corresponding to each character and a variable printing pitch. It is possible to print characters using this method.

[Brief explanation of the drawing]

FIG. 1 is an electrical block diagram of a dot matrix printer according to the present invention; FIG. 2 is a time chart showing an example of printing in the first printing mode; FIG. 3 is a time chart showing an example of printing in the second printing mode; FIG. 4A is an electrical block diagram showing a second embodiment of the present invention, and FIG. 4B is a time chart showing an example of printing in the second printing mode. In the figure, 5 is a memory, 7 is a printer head, and MOD _1.
is the first printing mode, MOD ₂ is the second printing mode, DPD is the dot pattern data, DT ₁ is the first timing data, and DT ₂ is the second timing data.

Claims (1)

[Scope of Claims] 1. A first printing device that includes a print head that moves along the printing line and prints all characters at a uniform printing pitch.
In a dot matrix printer capable of printing in two printing modes: a printing mode and a second printing mode in which each character is printed with variable printing pitch corresponding to each character, the dot pattern of each character is memorized, and the dot pattern of each character is memorized.
The first timing data that determines the printing timing from the beginning of the printing pitch of each character to the dot pattern printing start position of that character and the second timing data that determines the dot pitch of each character are used in the first printing process. A memory is provided for storing data common to each character for the mode, and data specific to each character for the second print mode in memory locations corresponding to each character. All the characters are printed using the common first and second timing data, and when in the second printing mode, the first and second timing data are printed using the unique first and second timing data corresponding to each character. A dot matrix printer characterized in that the dot pattern can be commonly used in both second printing modes.