JPS6150790B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feed control method for a line printer, and particularly to a paper feed control method suitable for setting printing paper before starting printing.

Figure 1 is an explanatory diagram of the printing style of a general line printer.
The pages are divided by , with 3 being the first page and 4 being the second page. Print start line 5 and perforation 2 of each page
The distance between the two jobs is fixed for each job, and in FIG. 1, d=d'. 6 is a feed hole for feeding paper. When printing, use the first
The paper 1 is set so that printing can be started from the print start line 5 in the figure.

Figure 2 is an explanatory diagram of the printing mechanism, where 7 is a type wheel, 8 is a printing hammer, 9 is an ink ribbon, and the printing hammer 8
By striking the paper 1 against the type ring 7 via the ink ribbon 9, the printed characters on the type ring 7 are transferred to the paper 1. Therefore, when starting printing, it is necessary to set the paper 1 so that the printing start line 5 is positioned opposite the printing hammer 8.

FIG. 3 is an explanatory diagram of the paper feeding mechanism. Paper feed shaft 1
By rotating the paper feed shaft 10, a tractor 11 fixed to the paper feed shaft 10 is rotated, and the paper 1 is fed. 6 row index disk 12 for 6 rows/inch to generate pulses of
and an 8-row/index disk 13 are mechanically connected and arranged. Row index disk 1
2 and 13 are provided with protrusions for generating row pulses, and an electromagnetic pickup 14 is provided close to the protrusions to generate a row pulse each time the respective protrusions pass. The pitch of the protrusions on the 6-row index disk 12 and the 8-row index disk 13 is 4:3.
In other words, the ratio is such that there are four protrusions on the eight-row index disk 13 to three protrusions on the six-row index disk 12. The row index disks 12 and 13 are attached so that the positions of the projections coincide with each other in the above-mentioned ratio. The situation is shown in FIG. 4 when developed linearly. On the other hand, the line control information is generally sent from the control device to the line printer after setting the paper 1 and before starting printing.

FIG. 5 is a flowchart showing the procedure up to the end of printing in a general case, in which the page break switch is activated in step M1, and the paper feed shaft 10 is operated until the output of the line control information storage device, which will be described later, reaches channel 1. Rotate. That is, the mechanical positions of the line control information storage device and the paper feed mechanism are made to match. In step M2, the paper 1 is set so that its printing start line 5 faces the printing hammer 8. In step M3, control information is transferred, in step M4, paper feed data and print data for one line are transferred, and in step M
At step 5, print and feed the paper to complete all printing.

FIG. 6 is an explanatory diagram showing the contents of the row control information. That is, it is transferred from the control device to the line printer as binary information consisting of six bits b1 to b6. Of these, b1 to b5 are sequentially written and stored in a row control information storage element using a random access memory or the like from address 0 to address (n-1). Leave the channel numbers for b1 to b4,
b5 represents an END flag, that is, a return to address 0 at the next address update. b6 has meaning only in the row control information of the first byte, and is written and stored in a register consisting of a flip-flop provided separately from the row control information storage element. If the bit b6 has a logical value of 1, then 1
The control information after the byte indicates that the line spacing is 8 lines/inch, and if the logical value is 0, then 6
Indicates the print line spacing in lines/inch. Row control information is transferred by n bytes, for example 6 bytes.
Paper 1 11 inches long with printed line spacing of line/inch
In this case, it is necessary to set n=6×11=66 bytes. The address of the row control information storage device is 6 rows/
In the case of a printing line spacing of inches, the information is updated by the detection pulse of the protrusion of the 6-line index disk 12 shown in FIG. It is updated by the detection pulse of the 13 protrusions. The line control information is used as an index to which position the paper should continue to be fed.For example, if a command is given to feed the paper to channel 1 in the transfer of paper feed data and print data in step M4 in FIG. For example, the paper feed operation is performed until the line control information storage device output becomes channel 1. The logic is configured in advance so that when the row control information advances to address (n-1), it automatically returns to address 0. Therefore, the print start line 5 in FIG. 1 is located at a position corresponding to the contents of address number 0 of the line control information storage device. In FIG. 6, the content of address 0 is a code indicating channel 1, which indicates that channel 1 is the index of the print start line.

FIG. 7 is a block diagram showing a schematic logical configuration in the above explanation. In Figure 7, 15
16 is a paper feed data register, 17 is a comparator, 18 is a paper feed flip-flop, 19, 23, 24 are AND gates, 21 is an address counter, 22 is an inverter, 25, 2
7 is an OR gate, and a detailed explanation of its operation will be omitted. However, in the conventional logical configuration,
When a page break switch (not shown) is pressed, the paper is simply fed until it reaches a channel number, for example, channel 1, corresponding to a predetermined print start line. In this case, there is no problem with line printers that do not have printing line spacing such as 6 lines/inch or 8 lines/inch, but with line printers that have printing line spacing that changes from 6 lines/inch to 8 lines/inch, there is no problem.
When switching from 8 lines/inch to 6 lines/inch, the distance between printing start line 5 on the first page and the second printing line is 1/6 inch or 1/6 inch. It is possible that it will not be 8 inches. As shown in FIG. 5, before setting the paper in step M2, the page break switch is activated and the paper is fed to the print start line 5 according to the line control information that has already been written. When there is no need to write line control information again, the line control information is not transferred, so the line control information storage device output is forced to the channel number corresponding to print start line 5, and matching with the actual paper position is performed. You will need it to take it. Here, for example, 6
Assume that the printing line spacing is changed from a line/inch to a printing line spacing of 8 lines/inch. Karini, 6
Assume that the position where the channel number corresponding to print start line 5 of the line control information in lines/inch is detected and paper feeding is stopped is the position corresponding to _P1 in FIG. 4. After setting the paper, line control information for 8 lines/inch is transferred, and then paper feed data and print data are sent, and printing and paper feed are repeated. Normal line spacing at 8 lines/inch is 1
Despite the inch/8 lines = 3.175mm/line,
In Fig. 4, the printing line spacing becomes 8 lines/inch from the P ₁ position, which moves to the P ₂ ′ position, and then P ₃ ′, P ₄ ′, etc., so the 1st line The printing interval for the second line is 1 inch/8 lines x 2-1 inch/6 lines≈2.117 mm/line, resulting in a deviation of 3.175-2.117=1.058 mm from the normal line interval.
Naturally, this also occurs when switching from a print line spacing of 8 lines/inch to a print line spacing of 6 lines/inch.

Conventionally, in order to eliminate such line spacing abnormalities, a switch to change the printing line spacing between 6 lines/inch and 8 lines/inch was provided, and this switch was always used when changing the line spacing. In order to adjust the mechanical position of the feeding mechanism, that is, the line index, to the printed line spacing after switching, it was necessary to operate a page feed switch or a line feed switch for feeding paper by one line. That is, there are disadvantages in that one page of paper is wasted or a cumbersome switching operation is required.

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper feed control method that eliminates the above-mentioned drawbacks of the prior art and allows the printing line spacing to be changed by a simple operation without causing abnormalities in the line spacing.

A feature of the present invention is that at least two types of row index signal generators each generate a row index signal and simultaneously generate row index signals when the ratio of the number of row index signals reaches a predetermined value. This was done with the aim of preventing abnormalities in the printing line spacing by switching the printing line spacing when a printout occurs, and also ensuring that the page break switch is activated when setting the paper before starting printing. When the page break switch is activated, the paper feed operation is performed until the output of the line control information storage device reaches the channel number corresponding to the print start line, and then the paper feed operation is performed from the respective line index signal generation devices. The output of the line control information storage device is controlled to be fixed at the channel number corresponding to the print start line until a line index signal is generated at the same time.

The present invention will be explained in detail below using the embodiment shown in FIG. FIG. 8 is a block diagram showing an embodiment of a paper feed control device to which the paper feed control method of the present invention is applied, and the same parts as in FIG. 7 are designated by the same reference numerals. As mentioned above, the present invention is designed to prevent line spacing from becoming abnormal even when the printing line spacing is changed, so the operations described below are performed before setting paper 1. It will be done. That is, this operation corresponds to step M1 in FIG.
Therefore, the following paper feeding operation refers to the paper feeding shaft 10.
is driven.

When you press page break switch 28, one shot 29
operates and a page break switch signal is sent out as a pulse signal. The flip-flops 30 and 31 are reset by this page break switch signal. Furthermore, although not shown in FIG. 8 to avoid complicating the explanation, paper feed data of the channel number corresponding to the print start line is created using this page break switch signal, and the paper feed data is input as paper feed data. A paper feed operation is performed only while the paper feed signal from the paper feed flip-flop 18 is at a logical value of 1 by writing in the data register 16 and generating a paper feed start signal. It is now assumed that the line control information input has already been transferred to the line printer and written into the line control information storage device 15. The 6th row index signal and the 8th row index signal are waveform-shaped pulse signals that are detected and generated by the electromagnetic pickup 14 in FIG. 3 every time the paper feed mechanism moves 1/6 inch and 1/8 inch, respectively. . The 6 lines/inch signal has a logic value of 1 for a print line spacing of 6 lines/inch.
This is a signal that becomes . When paper is fed at a printing line interval of 6 lines/inch, the AND gate 24 is opened by the 6 line index signal, but the 6 line/inch signal is converted to a theoretical value of 0 by the inverter 22. , AND gate 23 is not opened, and the 8th row index signal cannot pass through. The 6th row index signal passes through OR gate 25 and is applied to the input side of NAND gate 26. On the other hand, since the flip-flop 32 is reset by the paper feed signal with a logical value of 0, the 6th row index signal passes through the NAND gate 26, counts up the address counter 21, and inputs the address of the row control information storage device 15. Update. In this way, the address is updated every time one line of paper is fed, so the output content of the line control information storage device 15 changes to the output content for that address. One of the outputs becomes the input of the comparator 17, and the other one becomes the input of the channel decoder 20. Channel decoder 2
0, when the EMD flag is detected, the address counter 21 is reset to address 0 at the timing of the next 6 row index signal, so an END flag detection reset signal is generated and the OR gate 27 is reset.
input. At this time, address counter 21
Even if the 6-row index signal is input to the clock input, the reset signal is input to the RESET input terminal, so it will not count up because it has priority. Next, when the address of the address counter 21 returns to address 0, the row control information storage device 1
The output of No. 5 becomes a channel number code corresponding to the print start line, which is decoded by the channel decoder 20 in the same manner as described above, and is applied to the AND gate 33 and the one shot 34 as a print start line channel decode signal. One shot 34
is to pulse the print start line channel decode signal, the flip-flop 31 is set by the output of the one shot 34, the output of the NAND gate 35 becomes a logic value 0, the flip-flop 32 is set, and the NAND gate 26 closes the gate. . Therefore, the 6-row index signal generated by the subsequent paper feeding operation does not pass through the NAND gate 26, and the address counter 21 does not count up. That is, the output of the line control information storage device 15 remains the channel number code corresponding to the print start line. On the other hand, since the output of the line control information storage device 15 is input to the comparator 17, it is compared with the output of the paper feed data register 16 by the comparator 17. As mentioned above,
Since the channel number code corresponding to the print start line has already been written in the paper feed data register 16, both outputs match, and the comparator 1
The output of 7 becomes a logical value of 1. However, since the flip-flop 30 remains reset, the AND gate 19 does not open even at the timing of the sample pulse. Note that this sample pulse is a pulse signal generated by sufficiently delaying the output signal of the OR gate 25. This is done in order to prevent the AND gate 19 from opening before the output of the row control information storage device 15 etc. is determined, taking into consideration the element delay time of the row control information storage device 15 etc. be.

When the 6th row index signal and the 8th row index signal occur simultaneously, the AND gate 33 opens,
Flip-flop 30 is set. Therefore, the first output of the flip-flop 30 has a logical value of 1.
Then, the AND gate 19 opens at the timing of the sample pulse, the paper feed flip-flop 18 is reset, the paper feed signal becomes a logical value 0, and the paper feed operation ends. Furthermore, by resetting the paper feed flip-flop 18, the flip-flop 32 is also reset, and from now on, the passage of the 6-row index signal through the NAND gate 26 will not be obstructed.

The above is an explanation of the logic operation at 6 lines/inch, but for the logic operation at 8 lines/inch, the 6 line/inch signal has a logic value of 0, so
Same as above except that AND gate 24 is closed and AND gate 23 is open. Although omitted in the above explanation, the line control information transfer start signal and line control information transfer end signal are the transfer start signal and transfer end signal when line control information is transferred from the control device of the line printer to the line printer. , are signals for returning the address output of the address counter 21 to address 0.

The above is the operation corresponding to step M1 in FIG. 5 in the present invention, but after this, it is only necessary to set the paper according to the flow shown in FIG. That is, after that, line control information is transferred from the control device, then paper feed and print data are transferred, and normal printing and paper feed are performed alternately.

According to the embodiment of the present invention described above, a NAND gate 26 is connected between the OR gate 25 and the address counter 21, and a flip-flop 30 is reset by the page break switch signal when the page break switch 28 is pressed. , 31, and the flip-flop 30 is connected to the set terminal of the flip-flop 32 so that the paper-feed signal from the paper-feed flip-flop 18 is reset during logic 0, and its output at that time opens the NAND gate 26. The 0 side output of the flip-flop 31 and the 1 side output of the flip-flop 31 are inputted through a NAND gate 35, and the 1 side output of the flip-flop 30 is inputted to an AND gate 19. Further, the print start line channel code signal outputted from the channel decoder 20 after the paper feeding operation is completed is inputted to the AND gate 33 and the one shot 34 to which the 6th line index signal and the 8th line index signal are input, and the one shot is started. Set the flip-flop 31 at the output of 34, and
Flip-flop 30 is output from AND gate 33.
is set. Therefore, when the print start row channel decoder signal is output from the channel decoder 20, the flip-flop 32 is set and the NAND gate 26 is closed. However, at this time, flip-flop 30 remains reset, so AND gate 19 does not open.
Then, the paper feed flip-flop 18 is reset at the timing of generation of the 6th row index signal and the 8th row index signal. Therefore, the row control is continued until the timings of generation of the 6th row index signal and the 8th row index signal from the respective row index signal generators comprising the 6th row index disks 12, 13 and the electromagnetic pickup 14 shown in FIG. The output of the information storage device 15 is fixed to the channel number corresponding to the print start line. After that, even if the line control information is transferred and the print line spacing is changed,
Since the generation timings of the 6th line index signal and the 8th line index signal are stopped at the same signal, no line spacing abnormality will occur no matter what printing line spacing is switched. The operator is aware that the next printing job will be from 6 lines/inch to 8 lines/inch, and can switch using pre-programmed line control information without operating a switch, and can print at any line spacing. Even if the line spacing is switched, there will be no abnormality in the line spacing.

As explained above, according to the present invention, there is a remarkable effect that the printing line spacing can be changed with a simple operation without causing any abnormality in the line spacing.

[Brief explanation of the drawing]

Figure 1 is an illustration of the printing style of a general line printer, Figure 2 is an illustration of the printing mechanism, Figure 3 is an illustration of the paper feed mechanism, and Figure 4 is the 6-line index disk and 8-line index of Figure 3. A perspective view showing the positional relationship of the disks, FIG. 5 is a flowchart showing the operation and operation order of the line printer, FIG. 6 is an explanatory diagram showing the contents of line control information, and FIG. 7 is a line diagram of a conventional line printer. FIG. 8 is a block diagram showing a paper feed logical configuration based on control information. FIG. 8 is a block diagram showing an embodiment of a paper feed control device to which the paper feed control method for a line printer of the present invention is applied. In the figure, 1 is the printing paper, 5 is the printing start line,
10 is a paper feed shaft, 11 is a paper feed tractor, 12 is a 6-row index disk, 13 is an 8-line index disk, 14 is an electromagnetic pick-up, 15 is a line control information storage element, 16 is a paper feed data register, 17
is a comparator, 18 is a paper feed flip-flop, 1
9, 23, 24, 33 are AND gates, 20 is a channel decoder, 21 is an address counter, 22
is an inverter, 25, 27 are OR gates, 26,
35 is a NAND gate, 28 is a page break switch, 2
9 and 34 are one-shots, and 30, 31, and 32 are flip-flops.

Claims (1)

[Scope of Claims] 1. A page break switch, and at least two switches that each generate a row index signal and simultaneously generate the respective row index signals when the ratio of the number of the respective row index signals reaches a predetermined ratio. In a line printer that is equipped with a line index signal generating device of various types, a line control information storage device, and a printing line spacing switching function, the page break switch is operated in a state where no paper is loaded before paper is set. , the paper feed operation is carried out until the output of the line control information storage device becomes a channel number corresponding to the print start line, and a line index signal is simultaneously generated from each of the line index signal generation devices, and the line control information storage device A line characterized in that the output of the device is controlled to be fixed at a channel number corresponding to the print start line, and the line control information storage device and the plurality of line index signal generators are synchronized. How to control printer paper feed.