JPH0351148A - Printing control system of line dot printer - Google Patents

Abstract

PURPOSE:To increase the life of a printing head pin or a drive circuit by assigning a printing digital position shifted to each printing head pin when a faulty printing head pin is detected by shifting each printing head pin in relation to a printing digital position at random. CONSTITUTION:A printing digital position shift control device 24 generates, for example, the printing shift count of random numbers using a printing shift count generation device 25 each time, and controls the operation of a printer so that a train of dot data 20 is assigned to the printing head pin array 22 of a printing head 21 by shifting the train of dot data 20 by a printing shift count. Therefore, each printing head pin on the printing head 21 is forcibly shifted in relation to a printing digital position each time a time or a prearranged division for processing comes. Consequently, the printing head pin can be used uniformly and without unbalanced wear. Furthermore, the characteristic deterioration of the printing head is restricted and thereby its life is prolonged.

Description

[Detailed Description of the Invention] [Summary] The present invention relates to a print control method for preventing deterioration in print quality in a line dot printer that can print all dots simultaneously and in parallel by providing pins for one line of dots in the print head. .

The purpose is to extend the life of the printing hentbin and 1° live circuit in line dot printers, and to enable printing without any problems even if a defective part occurs in the print head pin or drive circuit. In order to prevent the correspondence from becoming fixed, the allocation of slots to the printing digit positions is sequentially shifted within a certain range, using the timing of an hour or a processing break as an opportunity.

In addition, when the power is turned on, each print head pin is inspected to see if it is good or bad, and if a defective print head pin is detected, the print digit position is assigned to the print head so that the print head pin is in the non-print area. Make it.

(Industrial Application Field) The present invention relates to a print control system for preventing deterioration of print quality in a line driver I printer that has pins for one line of dots in the print head and can print all dots simultaneously in parallel. It is something.

[Conventional technology]

As shown in FIG. 7, the conventional line 1 targeted by the present invention
The relationship between the print head pin arrangement and print output of a print printer will be explained.

In FIG. 7, 1 is the print head, 2 is the print head I/pin, 3 is the printing paper, and 4 is the driver I line. There are N number of printing slots 2, and each dot line 4 on the printing paper 3 is parallel to the one-dimensional array of the printing slots 2, and printing is performed while feeding the printing paper 3 in line in the direction of the arrow in the figure. Printing is accomplished by driving the appropriate print bin according to the dot pattern of the desired character. The character position of each print line is fixed according to the initial settings.

FIG. 8 shows the configuration of a conventional line dot printer.

In FIG. 8, 5 is an MPJ for printing control, 6 is a ROM in which the printing system j1 program and character pattern patterns are stored, 7 is a RAM for developing input print data and pattern patterns, and 8 9 is a manual port for inputting print data and commands from the host device; 9 is an output port for outputting control signals to each part of the printer mechanism; 310 is a line feed pulse motor that feeds printing paper dots and line feeds; 11 is l.
N free memory stores that store dot data for dot lines.
A shift register consisting of buffers FFI to FFN,
12 is a gate circuit that controls printing timing; 13 is a drive circuit consisting of N switching transistors that drives the yF bin for each print.

14 is the head resistance of the nodule pin for each print.

The head resistor 14 is a heating resistor if the print head is of a thermal printing type, and is a driving resistor if the print head is of an impact type. Next, the operation of the print control circuit shown in FIG. 8 will be explained with reference to the print timing chart shown in FIG.

The MPL 15 stores in the RAM 7 one line of print data that is manually input sequentially on the input boat date, and first develops it into a tondo pattern. Then, the dot data of 1 ton] - line j'' is outputted from the output port 9 along with the clock as shown in Fig. 9, and is sent to the shift I register 11. The don't position is filled with the value of white dot 1.

The M I'U 5 outputs the enable signal shown in (■) in FIG. The data is transferred in parallel to the drive circuit 13, and the printing head pin is driven to print the L dot line.Subsequently, as shown in (2) in FIG.

A line feed control signal B is sent from the output boat 9 to the line feed pulse motor IO to perform a dot line line feed. If there is dot data on that dot line, the above operation is repeated.

[Problem to be solved by the invention]

In conventional dot line printers, the printing start position and each printing digit position in each printing line are often almost fixed, and the printing gutter pin corresponds to this, and the printing gutter pin is also adjusted to the vertical ruled line position. There are print head pins that are used all the time, such as the print head pins that are used all the time, and print head pins that are never used, such as the print head pins that correspond to the left and right margins and the gaps between characters.

Therefore, frequently used printing pins and their corresponding drive circuits are prone to performance deterioration and failure.
There is a problem in that it shortens the life of the print head pins and drive circuit, and also reduces print quality.

An object of the present invention is to extend the life of print head pins and drive circuits in line dot printers, and to enable printing to be performed without any trouble even if a defective part occurs in the print head pins or drive circuits.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention randomly or cyclically shifts the correspondence between each print head pin and the print digit position so that the seat pin and drive circuit are not overused for specific printing. In addition, the characteristics of the seat pin for each print are monitored, and if a seat pin is detected for a defective print, the print digit position for each print head pin is shifted and assigned so that the print head pin does not overlap the print digit position. This is what I did.

The present invention will be explained in detail with reference to FIGS. 1(a) and 1(b).

FIG. 1(a) shows the basic configuration of a line dot printer according to the first invention, which has a print shift function that sequentially shifts the correspondence between the print digit position and the print position pin. ), 20 indicates a dot data string for 4 pages, 21 is a print head, 22 is a print head bin row, 23 is printing paper, and 24 is a dot data string for each appropriate operation in time or processing. Site data column 20
25 is a print shift number generating means that generates a print shift number randomly or cyclically within a certain range.

Here, the print digit position shift control means 24 is activated, for example, at the time of initialization processing when the power of the dot line printer is turned on. Control B is performed so that in subsequent printer operations, the dot data row 20 is shifted by the print shift number and assigned to the print head pin row 22 of the printing spatula F21.

FIG. 1(b) shows the characteristics of cytopine for printing as determined by 4).

The second part has the function of shifting the printing digit position according to the result.
1 shows the basic configuration of a line don't printer according to the invention.

In FIG. 1(b), 26 is a characteristic measuring means for measuring the characteristics of each print head pin in the row of print head pins 22 and detecting the print head pins with poor characteristics. When detected, the printing digit position shift control means shifts the correspondence between the dot data row 20 and the print dot pin row 22 so that the pin position is removed from the printing digit position.

(Function) According to the configuration of the first invention shown in FIG.
It is forcibly shifted each time a predetermined break occurs in time or processing.

For example, even if you are printing out a large number of documents with the same format every 8 days, you can set appropriate delimiter conditions to shift the print digit position for each printout, for each printout, or for each printout. By setting ζ, it is possible to prevent the seat pins from being overworked for regular printing, and to avoid shortening the lifespan of some of the print head pins and drive circuits due to excessive wear.

Also, as the shift number of the print digit position, a random number or fi
By using the ring number, it is possible to equalize the 1llJ on the cytopin side to the printing as much as possible.

FIG. 2(a) shows a specific example of the printing digit position shift.

(2) is a) J f1 position, (2) is a printing state shifted by two dots to the right, and (5) is a printing state shifted two dots to the left.

Next, according to the configuration of the second invention shown in FIG. Since the printing digit position is shifted manually or manually, it is possible to prevent a drop in printing quality due to missing dots or unclear printing.

Figure 2(b) shows a specific example of this. This shows the state in which missing printing has been eliminated.

[Embodiment] FIG. 3 shows an embodiment of the first invention shown in FIG. 1(a).

In FIG. 3, the components indicated by reference numbers M to 14 are the same as those shown in the conventional example of FIG. 8 with the same reference numbers, and the basic operations are also the same, so here Here, duplicate explanations will be omitted.

In FIG. 3, 30, a newly added component according to the present invention, is a random number generation circuit, which generates a print shift number using random numbers. 31 is an initialization program;
Performs printing shift number setting processing when turning on the Til source, 32
is the set print shift number.

FIG. 4 shows the configuration of the second embodiment (Part 1) of the second invention shown in FIG. 1(b).

In FIG. 4, the components designated by reference numbers 5 to 14 are the same as those shown in the prior art example of FIG. To explain the newly added components in FIG. 4, 40 is either the drive voltage 24V of the head resistor 14 of the linter print head on the constant current circuit side that generates a constant current of 5 mA, or the constant current of 5 mA. 42 is a voltage detection circuit that measures the voltage generated across the head resistor 14; and 43 is a diagnostic program.

In the initialization process when the power is turned on, the diagnostic program 43 switches the relay switch 41 to the constant current circuit 40 side, supplies the print head pin scanning data and shift clock to the shift register 11, and sets the print head pin placement stand. Diagnose.

Therefore, each switching transistor of the drive circuit 13 is sequentially turned on one by one by the scanning pulse from the shift register 11, and a constant current of 5 mA is caused to flow through the corresponding head resistor 14.

At this time, the voltage detection circuit 42 detects the voltage across the series circuit of the head resistor and the switching transistor and inputs it to the five-person port 8.

The normal value of the head resistor 14 is, for example, 100 ohms, and in this case, if both the head resistor and the switching transistor are normal, the voltage detection circuit 42 detects a voltage of 0.5 volts.

The diagnostic program 43 takes in the voltage detected by the voltage detection circuit 42 regarding the head resistance of each of the seven print head pins,
Determine pass/fail. If there is a head resistance that shows an abnormal value, a mode is set to shift the print digit position by an appropriate dot in order to prevent the rad pin from being used for that print. In this case, if the dot width of the printed character is 5 dots, it is sufficient to shift within the range of -3 to +3 dots.

The operation mode in which the printing control is controlled by one step by shifting five printing digit positions in this way will be referred to as the print shift mode, and the operation mode in which no shifting will be performed will be referred to as the print no. 1 shift mode. Next, the operation of the embodiment shown in FIG. 4 will be explained in detail with reference to the flow shown in FIG.

First, when the power is turned on and startup is performed, the relay switch 41 is switched to the constant current circuit side.

A counter N is provided to sequentially check the rad pins for printing.
Initialize N=1, turn on F and Fl of shift register 11, turn off F, F2~FN, and turn on the enable signal.This drives only the print head pin in the first slot. A constant current is passed through the - node resistor (4).The voltage at that time is detected by the voltage detection circuit 42, and it is determined whether the voltage is normal or abnormal.

If a normal voltage is detected, the 5 counter N is incremented to 2 and the Rad pin is diagnosed for the second printing.Thereafter, as long as the voltage is normal, the counter is incremented and the diagnosis is made sequentially up to the last head. Then, set the printing non-shift mode to 1°.

On the other hand, if abnormal voltage is detected, the number of print shifts (-
3 to +3) and set the print shift mode for that value.

When the following processing is completed, the (V) of the printing operation is made ready, and each time a print command is received, printing is controlled according to the set print shift mode or print shift mode.

In the embodiment (part 1) of FIGS. 4 and 5 described above,
Although the number of printing shifts is determined automatically, it is also possible to manually specify the number.

FIG. 6 shows a manual embodiment (Part 2).

In FIG. 6, numeral 44 is a switch for setting the number of printing shifts, and a low-return switch, dip switch, or the like is used. Then, during the initialization process, the set value of the switch 44 is read via the manual boat 8, and if the set value is 0, the print shift mode is set.

(Effects of the Invention) In the dot line printer according to the present invention, the use of print head pins can be equalized, thereby eliminating the extreme imbalance caused by wear of the print head, suppressing deterioration of print head characteristics, and extending the life of the print head. I can do it.

Furthermore, even if a certain printing head pin is torn, the printing digit position can be shifted to a position where no problem occurs, so printing quality and maintenance performance can be improved.

[Brief explanation of drawings]

Figure 1 (a) is a diagram of the principle configuration of the first invention, Figure 1 et al.)
FIG. 2(a) is an explanatory diagram of a specific example of the printing digit position shift according to the first invention. FIG.
) is an explanatory diagram of a specific example of the printing position shift I according to the second invention, FIG. 3 is a configuration diagram of the embodiment of the first invention, and FIG.
The figure is a block diagram of the embodiment (part 1) of the second invention, FIG. 5 is a flow diagram of the embodiment (part 1) of the second invention, and FIG. 2), FIG. 7 is an explanatory diagram of the relationship between the rad pin arrangement for printing and print output, FIG. 8 is a diagram of the configuration of a conventional example of a line dot printer, and FIG. 9 is a print timing diagram of the conventional example. FIG. 1(a), (in 111. 20: Dot data row 21: Print head 22: Print head bin row 23; Print paper 24.27: Print digit position shift control 'B means 25: Print shift number generation means 26: Characteristic measurement means

Claims (4)

[Claims] (1) In a line dot printer in which the print head is equipped with print head pins that correspond one-to-one with each dot of one print line and can print all dots of one dot line simultaneously and in parallel, the above print head pins and print A printing control method characterized by sequentially shifting the allocation of print head pins to printing digit positions within a certain range, triggered by time or processing breaks, so that the correspondence with digit positions is not fixed. (2) The print control method according to claim 1, wherein the correspondence between the print head pin and the print digit position is shifted each time the power is turned on. (3) A print control system according to any one of claims 1 and 2, further comprising a random number generation circuit, and shifting the correspondence between the print head pin and the print digit position in accordance with the random number generated by the random number generation circuit. (4) In a line dot printer where the print head is equipped with print head pins that correspond one-to-one with each dot of one print line and can print all dots of one dot line simultaneously and in parallel, each A printing control method characterized by inspecting whether a printing head pin is good or defective, and when a defective printing head pin is detected, assigning printing digit positions to the printing head pin so that the printing head pin is in a non-printing area. .