JPH01178455A - Dot printer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dot printer that prints out one line of dot data by dividing the data into two parts when the current consumption becomes large. .

[Prior Art] As shown in FIG. 7, a print head 1 of a dot printer has a plurality of dot pins 2 arranged vertically. For example, when the character code [A] is input from an external host computer, the character generator generates [
A] dot pattern is read out and each dot bin 2 is energized at a timing corresponding to the dot pattern while the print head 1 is moved at a constant speed in the lateral direction to obtain the dot pattern characters shown in FIG.

Note that there are cases where the host computer inputs the dot data indicating the character shape instead of the character code format. In this case, the input dot data may be printed out as is by the print head 1.

[Problems to be Solved by the Invention] However, even with the above-mentioned dot printer that uses all the dot bins 2 to print out one line of characters at all times, there are still the following problems to be solved. . In other words, when printing out one line of characters using a dot printer using such a print head 1, if each character making up this one line is formed of a complex kanji character with many strokes, In this case, the number of times the dot bin 2 is energized per unit time increases. Conversely, if one line is formed of characters with relatively few strokes, such as alphabetic characters, numbers, and kana, the number of times the dot pin 2 is energized per unit time is small.

Therefore, the capacity of the power supply device for energizing the dot pins 2 needs to have a power supply capacity corresponding to the number of times of energization corresponding to the case where the kanji characters are consecutive. As a result, a large-capacity power supply device, which is rarely used in dot printers, is incorporated, increasing weight and manufacturing costs.

In the present invention, when the current consumption value exceeds the specified value during printing,
To provide a dot printer that can reduce the maximum capacity of the required power supply, make the entire device smaller and lighter, and reduce manufacturing costs by printing twice on the unprinted dot data after that position. The purpose is to

[Means for Solving the Problems] As shown in FIG. 1, the dot printer of the present invention has a print buffer A that stores one line of dot data to be printed out, and controls movement along a platen B. A dot printer that prints out dot pattern characters on print paper set on a platen based on dot data in a print buffer using a print head C in which a plurality of dot bins are arranged vertically, including the print head from the power supply section. Detecting the current value of the current supplied to each electronic component,
An overcurrent detection circuit E outputs an overcurrent detection signal when this current value exceeds a specified value, and in response to the overcurrent detection signal output from this overcurrent detection circuit, the current position of the print head is set as the detection position. In response to the detected position memory F to store and the overcurrent detection signal, dot data corresponding to a preset number of dot pins among the plurality of dot pins in the unprinted dot data in the print buffer is printed up to the final position of that line. In response to the limited dot row print output means G to output, and the end of the print output of dot data by this limited dot row print output means, the print head is moved to a detection position, and unprinted dots in the print buffer are printed from the detection position. The remaining dot row printout means H executes printout of the data.

[Operation] In the dot printer configured as described above, the current value of the current supplied from the power supply section to each electronic component including the print head is constantly monitored by the overcurrent detection circuit. In the process of printing out one line of dot data stored in the print buffer using the print head, many characters with many words such as kanji appear and the current value reaches the specified value. A current detection signal is output.

When the overcurrent detection signal is output, the current position of the print head is stored as the detected position. Thereafter, the unprinted dot data in the print buffer is divided into two parts and printed out by the limited dot row print output means and the remaining dot row print output means. As a result, the current value consumed by the print head per unit time is approximately halved, and the total current value can be almost prevented from exceeding a specified value.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a plot diagram showing the dot printer of the embodiment. In the figure, reference numeral 3 denotes a power supply unit that supplies a DC drive voltage VD to each electronic component of the dot printer including the print head 1. The drive voltage VD output from the power supply unit 3 is supplied to a print head drive circuit 4 and a motor drive control circuit 5 that control energization of exciting coils that drive each dot pin 2 of the print head 1.

In the print head 1, as shown in FIG.
For example, 24 dot bins are arranged vertically,
Each dot pin 2 is driven by energizing the corresponding excitation coil, and one dot is printed on a printing paper set on a platen via a printing ribbon.

The motor drive control circuit 5 also includes a paper feed (PF) motor 7 that feeds the printing paper set on the platen, and a carrier (PF) that controls the movement of the carrier on which the print head 1 is mounted in the axial direction along the platen. CA) Motor 8 etc. are connected.

Further, an overcurrent detection circuit 10 is connected to a current supply path 9 from the power supply section 3 to the print head drive circuit 4 and motor drive control circuit 5. This overcurrent detection circuit 10 is
A current value l flowing through the current supply path 9 is detected, and when this current value I reaches a specified value set with a certain margin with respect to the maximum current capacity of the power supply section 3, an overcurrent detection signal is output. This overcurrent detection signal is input to a print control section 11 composed of, for example, a microprocessor.

Further, dot data input from an external host computer 12 to this dot printer with characters to be printed converted into dot bark is received by a receiving section 13 and then manually inputted to a storage section 14. As shown in FIG. 3, this storage section 14 includes a reception buffer 14a that temporarily stores the dot data received by the reception section 13, and one line of dot data to be printed on the printing paper set on the platen. A detection position memory 14c is formed to store, as a detection position P, the current position of the print head 1 indicated by the carrier position at the time when the overcurrent detection signal is output from the overcurrent detection circuit 10.

The print control section 11 executes various information processing based on various commands and data input via the reception section 13 and overcurrent detection signals input from the overcurrent detection circuit 10, and also executes various information processing based on the overcurrent detection signal inputted from the overcurrent detection circuit 10. 4 and the motor drive control circuit 5.

Note that the power supply section 3 includes an overcurrent detection circuit 10. Print control section 11. A control voltage V is applied to the receiving section 13 and the storage section 14.
C, but their power consumption is extremely small.

The print control unit 11 is programmed to execute print processing on dot data input from the host computer 12 in accordance with the flow chart shown in FIG.

When the flowchart is started, the host computer 1 at Pl
One line of dot data is read out from the dot data transmitted from No. 2 and stored in the reception buffer 14a, and set in the print buffer 14b. Then, the carrier (CA) motor 8 is activated in the forward direction via the motor drive control circuit 5. However, the print head 1 mounted on the carrier
starts moving along the platen. When the print head 1 starts moving, one dot worth of data is sent to each of the 24 dot bins 2 arranged in the vertical direction of the print head 1 at P2. Then, one row of dots is printed on the printing paper.

Then, at this point in P4, the overcurrent detection circuit 10
Check whether an overcurrent detection signal is output from the

If the overcurrent detection signal is not output, the current value is less than the specified value, so if you confirm in P4 that the printout process for all dot data for one line has not been completed, P2 Return to step 1 and start printing for the next one dot row.

When the print output process for all dot data for one line is completed in P4, the print buffer 14 of the storage unit 14 is
Clear b. Then, at P6, the reception buffer 14a
The existence of dot data that has not yet been printed out is checked, and if it exists, the process returns to Pl. If it does not exist, this printing process ends.

Further, when the overcurrent detection signal is output at P3, the current position of the print head 1 indicated by the current carrier position is stored as a detection position P in the detection position memory 14c at P7. After that, in P8, among the unprinted data in the print buffer 12b, for example, only the upper 12 dot data corresponding to the upper 12 dot pins 2 out of the 24 dot bins 2 are used to correspond to the lower 12 dot pins 2. Lower side 12
Block out the dot data. Then, one vertical column of dot data corresponding to the upper 12 dot pins 2, that is, 12 dot data is printed. Then, printing is performed in the limited dot row state up to the final position of one line.

When the final position of one line is printed, the carrier motor 8 is stopped at P9. Then, the carrier motor 8 is started in the reverse direction to return the print head 1 mounted on the carrier to the detection position P stored in the detection position memory 14c.

Then, the carrier motor 8 is activated in the forward direction to start moving the print head 1 in the forward direction. Previously shielded at PIO (
The print output for the 12 dot data for the lower 12 dot pins 2 that have not been printed out due to the restriction) is started. Then, when the print output to the final position of one line for the remaining dot columns from the previous time is completed, the print output of all the dot data for one line to the print buffer 14b is completed, so the process advances to P5, and the print buffer 14b is clear.

According to the dot printer configured in this way, if the characters in one line have relatively few characters such as alphabets and numbers, the current value I will never reach the specified value, so the current value I will not reach the specified value, as shown in FIG. 5(a). As shown, all 24 dot pins 2 of print head 1
It is printed out in one go using .

In addition, if characters with many lexical characters such as kanji are mixed in the middle of one line, the current value I reaches the specified value from the middle of the line, so the specified value At the point in time (detection position P), the printing control shifts from one-time printing to two-time printing. That is, as shown in Figure (C), only the upper dot data is printed from the detection position P to the final position of one line, and then the remaining lower dot data is printed as shown in Figure (d). be done.

In this way, the current value! When the current value I reaches a specified value, the number of dot pins 2 that perform printing and operation is halved at that point, thereby suppressing the increase in the current value I.

Therefore, it is not necessary to set the maximum capacity of the power supply unit 3 so that one line of characters corresponds to kanji characters with many words and phrases. For example, in the embodiment, the current capacity may be set to a value slightly higher than the intermediate value between the current capacity when no printing operation is performed and the maximum current capacity when printing Chinese characters with many words.

Therefore, the power capacity of the power supply section 3 can be reduced.

As a result, the entire device can be made smaller and lighter, and manufacturing costs can be reduced.

FIG. 6 is a diagram showing print output control for one line of dot data when the present invention is further expanded. In this case, one line is divided into a maximum of four times and printed out. Therefore, the specified value that determines the current value (2) at the time when the overcurrent detection signal is output is set to a value that is much lower than the specified value in the previous embodiment.

First, as shown in FIG. 2A, printing is started using all dot bins 2 of the print head 1. Then, the detection position P1
When an overcurrent detection signal is output at
The upper 12 dot pins 2
Printing of 12 dot data corresponding to 1 is started. Then, as shown in the same figure (c), when the overcurrent detection signal is output again at the detection position P2, the lower 6 dots of the 12 dot data corresponding to the upper 12 dot pins 2 are output. 6 dot data corresponding to dot pin 2 is shielded. Finally, only the dot data corresponding to the six dot pins 2 from the top are printed out to the final position of one line.

After that, as shown in (d) of the same figure, among the remaining dot data, the intermediate dot data after the detection position P2 is printed out. Start printing the dot data.

Then, when the overcurrent detection signal is output again at the detection position P3, the remaining dot data is again divided into halves and printed out as shown in FIGS. 6(f) and (g).

In this way, by dividing one line of dot data stored in the print buffer 14b into smaller pieces according to the current value (■) and printing them out, the power capacity of the power supply section 3 can be reduced without considering the printing speed. can be made even smaller.

[Effects of the Invention] As explained above, according to the dot printer of the present invention,
When the current value reaches a specified value during printing, printing is executed twice for unprinted dot data after that position. Therefore, the maximum capacity of the required power source can be reduced, the entire device can be made smaller and lighter, and manufacturing costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a functional block diagram showing the configuration of the present invention, FIGS. 2 to 5 show a dot printer according to an embodiment of the present invention, FIG. 2 is a block diagram, and FIG. 3 is a storage unit. 4 is a flowchart showing the operation, FIG. 5 is a diagram showing the printing procedure, FIG. 6 is a diagram showing the printing control procedure in a dot printer to which the present invention is applied, and FIG. 8 is a diagram showing a general print head, and FIG. 8 is a diagram showing dot perk characters. DESCRIPTION OF SYMBOLS 1... Print head, 2... Dot pin, 3... Power supply part, 4... Print head drive circuit, 5... Motor drive control circuit, 8... Carrier motor, 9... Current 10... Overcurrent detection circuit, 11... Printing control unit,
14...Storage unit, 14a...Reception buffer, 4b.
...Print buffer, 14c...detection position memory. Applicant's agent Patent attorney Takehiko Suzue Figure 3 Figure 7 Figure 8

Claims (1)

[Claims] It has a print buffer that stores dot data for one line to be printed out, and based on the dot data in the print buffer, a print head whose movement is controlled along the platen and has a plurality of dot pins arranged in the vertical direction, In a dot printer that prints out dot pattern characters on printing paper set on the platen, the current value of the current supplied from the power supply unit to each electronic component including the print head is detected, and this current value is determined as a specified value. An overcurrent detection circuit outputs an overcurrent detection signal when the overcurrent detection signal is output, and a detection position memory stores the current position of the print head as a detection position in response to the overcurrent detection signal output from the overcurrent detection circuit. , in response to the overcurrent detection signal, print out dot data corresponding to a preset number of dot pins among the plurality of dot pins in the unprinted dot data in the print buffer up to the final position of the line. A limited dot row print output means, and in response to the completion of print output of dot data by the limited dot row print output means, moves the print head to the detection position, and prints unprinted dots in the print buffer from the detection position. A dot printer comprising a remaining dot row printout means for printing out data.