JPS63212578A - Printer - Google Patents

Abstract

PURPOSE:To prevent a printing position on a continuous sheet from displacing by setting the value of a counter for storing the theoretical printing position on a sheet to a reference value when indexes provided at an equal interval on the sheet with respect to the feeding direction of the continuous sheet are detected. CONSTITUTION:An encoder 41 detects the rotational angle of a motor 40 to detect the position of the row direction of a print head 28. A photocoupler 15 radiates light to an optical mark 50 bonded to the position of a sewing seam 51 of a continuous sheet 47 for reflecting the light to detect the reflected light. Since a present row C stored in a row counter 8 is set to '0' of a reference value when a detection signal of the mark 50 from the photocoupler 15 is input, the displacement of the printing position is not accumulated.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a printing device for printing on continuous paper that prevents misalignment of printing positions caused by accumulation of mechanical line feed errors.

[Prior art]

Conventionally, the paper feeding mechanism for continuous paper in printing devices involves sprockets provided at equal intervals on the edge of the paper engaging with a sprocket wheel, and this sprocket wheel is rotated by a drive motor to feed the paper. . The paper feeding position is controlled by the rotation angle of this drive motor.

[Problems to be solved by the invention]

However, between the sprocket wheel and the drive motor,
Although a force transmission mechanism such as a gear is involved, due to play in gears and mechanical parts, the relative rotation angle commanded to the drive motor at each line feed, that is, the commanded paper feed amount and the actual paper feed amount. This causes a discrepancy between the two. Since the relative rotation angle of the drive motor is given as an incremental value, in the case of continuous paper, this deviation in the paper feed amount for each line feed accumulates, causing the print position to not be as designed and causing a decline in print quality. It became.

[Purpose of the invention]

The present invention has been made to solve the above-mentioned problems, and its purpose is to prevent misalignment of printing positions on continuous paper.

[Means to solve the problem]

The configuration of the invention for solving the above problems includes a paper feeding mechanism that feeds continuous paper, a counter that stores the print position in the feeding direction of the paper, and a value of the counter that is updated according to the drive amount of the paper feeding mechanism. In a printing device having a print position counting means, a detection means detects marks on the paper provided at equal intervals with respect to the paper feeding direction, and when the marks on the paper are detected by the detection means. , and setting means for setting the counter value to the reference value.

[Effect]

The print position counting means updates the value of the counter according to the drive amount of the paper feeding mechanism, for example, the incremental rotation angle of the drive motor, and the value stored in the counter becomes the theoretical print position of the paper. The detection means detects an index provided on the continuous paper. This index provides a reference position for repeating a sheet of paper, for example, a reference position for one page. Specifically, this index includes a perforation, a set of sprocket holes in a certain number, an optical mark placed at the same position on each page or every few pages, and an optical mark placed in multiple parts on one page. It is a set of each fixed number of . The setting means sets the value of the counter to a reference value when the indicator on the paper is detected by the detection means. This reference value is the theoretical value when an index is detected in an ideal state with no deviation.
This is the printing position. Therefore, as the continuous paper is fed, a difference occurs between the counter value, that is, the theoretical print position and the actual print position, but the counter value is set to the reference value each time an index is detected. Therefore, the theoretical printing position and the actual printing position match at this point. Therefore, since errors in the feed amount do not accumulate, the printing position becomes accurate.

【Example】

The present invention will be described below based on specific examples. FIG. 2 is a perspective view showing the mechanism of the printing section of the printer. In the figure, the print head 2 is mounted on the carriage 26.
8 and a paper presser 2 that turns the paper along the platen 25
7 are arranged. The carriage 26 is the guide bar 4
4.45 and moved horizontally by a belt 46. Belt 46 is driven by motor 40 via pulley 42 . An encoder 41 is coupled to the motor 40, and the encoder 41 detects the rotation angle of the motor 40 to detect the position of the print head 28 in the row direction. Furthermore, sprocket wheels 49 are disposed on both sides of the platen 250 and are engaged with the sprocket holes 48 of the continuous paper 47, and the sprocket wheels 49 are driven by the paper feed motor 12 (FIG. 1) through a transmission mechanism (not shown). rotated. Further, on the left side of the platen 25, a photocoupler 15 is mounted on the frame 23, which irradiates light onto an optical mark 50 that reflects light and detects the reflected light, which is pasted at the position of the perforation 51 of the continuous paper 47. It is installed protrudingly. FIG. 1 is a block diagram showing the electrical configuration of the printer of this embodiment. A ROM 4 that stores a print processing program and a RAM 6 that stores print data and control data are connected to the central processing unit 1 (CPU).
M6 is provided with a reference value memory 7 for storing a reference value, a line counter 8 for storing a theoretical printing position in the paper feeding direction of the carriage 26, and a page counter 9 for storing a theoretical page. Also, CPU 11. : C each driver 2.10,1
1 are connected, and these drivers drive a motor 40 for moving the carriage, a motor 12 for paper feeding, and a solenoid 13, respectively. Motor 12 rotates sprocket wheel 49 to feed the paper. Also, solenoid 13
drives the impact wire to print a dot pattern on the paper. Motor 40 moves carriage 26 horizontally. Further, the photocoupler 15 is supplied with power from the power supply 18, and the detection signal of the optical mark 52 is input to the CPU 1. Next, the operation of the printer of this embodiment will be explained based on the flowchart shown in FIG. First, when the print position is commanded to be the second line of page 8 (this number of lines uses the mechanical minimum feed as the basic unit of one line), this paper feed program is started. below,
In the program, the page at the commanded print position is called command page S, the print line is called command waiting P, the value stored in line counter 8 is called current line C1, the value stored in page counter 9 is called current page That's what it means. In step 10G, it is determined whether the current page and the command page S are equal or not. If they are equal, steps 102 and subsequent steps are executed as same page processing. In step 102, it is determined whether the current line C is greater than or equal to the command line P. If C≧P, the command-waiting P exists before the current line C on the same page, and forward paper feeding is impossible, so the process ends. On the other hand, in the case of CP, command waiting P
Since line C is ahead of current line C on the same page, paper feeding is possible, and the process moves to step 104, where the paper feeding motor 12 is driven in normal rotation by a unit angle. Next, step 10
At step 6, the current row C is updated by the amount of movement. Then, in step 108, it is determined whether an optical mark detection signal has been input from the photocoupler 15. If the detection signal is not input, the process returns to step 102 and the above process is repeated, and the paper is fed until the current line C becomes equal to the command waiting P. In step 102, the current line C
If it is determined that is equal to the command waiting P, it means that paper feeding has been executed up to the command waiting P, and this process ends. Also, when an optical mark is detected during paper feeding, the determination in step 10B is YflS,! :Nari, step 1
10, the current line C is set to the standard value 0,
If the current page and command page S are equal in the next step 112, the process moves to step 114 and the process ends. That is, in the case of the command page S that is the same as the current page, even if the condition of current line C=command line P is not satisfied during sheet feeding, the sheet will be fed to the bottom line of the page. This discrepancy would be caused by a mechanical feed error if there was no error in the command, but this kind of processing prevents the error from spreading to the next page. On the other hand, if the current page and the command page S are not equal, this means that the paper will be fed to a page different from the current page, and the actual position of the paper will be the next one when this optical mark is detected. Since it can be regarded as the first line (line 0) of the page, the process moves to step 116, where the current page is incremented by 1, and the process moves to step 100, where the current page and the command page S are compared. It will be done. When the current page becomes equal to the command page S, the process moves to step 102 and the above processing is executed as described above. On the other hand, if it is determined in step 100 that the current page and the commanded page s2 are not the same, the process jumps to step 104 without executing the process in step 102. That is, when the current page has not yet reached the command page S, the bottom line of the current page,
That is, the page is changed by feeding the paper to the printing position where the optical mark is detected. As described above, in this embodiment, the current line C is set to the reference value O every time an optical mark is detected, so that the deviation of the printing position does not accumulate. In the above embodiment, for simplicity, the optical mark is detected at the page break position, but the optical mark does not necessarily need to be pasted at the page break location, and it is detected from the first line of the page. It only needs to be in a certain position. Further, when the perforation is used as an index, the detection means is a device that brings a sensor or roller that optically detects the perforation into contact with the continuous paper and detects the operation of a tension bar connected to the roller. Good too. Furthermore, the detection of a certain number of sprocket holes may be used as an indicator detection.

【Effect of the invention】

The printing device of the present invention includes a detection means for detecting marks on the paper provided at equal intervals in the feeding direction of continuous paper, and when the marks are detected by the detection means, a theoretical printing position on the paper. Since the counter value is set to the reference value when an index at a certain printing position on the paper is detected, the counter value is set to the reference value. Since the error between the actual print position and the theoretical print position disappears each time the index is detected, accumulation of errors is prevented, and the print position becomes accurate.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the electrical configuration of a printer according to a specific embodiment of the present invention. FIG. 2 is a mechanical diagram showing the mechanical configuration of the printer. FIG. 3 is a flowchart showing the processing procedure of the CPU used in the printer. 23... Frame 25... Platen 26...
・・Carriage 27・・Paper presser 28°・Print head 44.45゛・Paper guide par 46・・・
Belt 47...Continuous paper 48...Sprocket hole 49...Subrocket wheel 50...Optical mark 51...Perforation 15...Photocoupler

Claims (4)

[Claims] (1) Printing that has a paper feeding mechanism that feeds continuous paper, a counter that stores the printing position in the feeding direction of the paper, and printing position counting means that updates the value of the counter according to the amount of drive of the paper feeding mechanism. In the apparatus, a detection means for detecting indicators on the paper provided at equal intervals with respect to the feeding direction of the paper, and when the indicators on the paper are detected by the detection means, the value of the counter is used as a reference. A printing device comprising a setting means for setting a value. (2) The printing device according to claim 1, wherein the detection means is a photosensor that detects reflected light from an optical mark provided at an end of the continuous paper. (3) The printing device according to claim 1, wherein the detection means is a device for detecting perforations in the continuous paper. (4) The printing device according to claim 1, wherein the detecting means detects the number of paper feeding holes provided at an end of the continuous paper.