JP2005035228A - Control system of tandem connection cut paper laser beam printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance printing position precision corresponding to the shrinkage of paper independently produced longitudinally/laterally even in the spot color printing in a tandem connection cut paper laser beam printer without adjusting the quantity of image dot data. <P>SOLUTION: The shift of a printing position in spot color printing caused by the shrinkage of a paper sheet passed through a fixing part is independently adjusted at every printing of each page based on the shrink quantity of the paper sheet in both londitudinal and lateral directions of the paper sheet in a cut paper laser beam printer on a front side and a cut paper laser beam printer on a rear side by performing the fine adjustment of a paper feed speed at the time of transfer of toner to the paper sheet from a paper drum and the fine adjustment of the frequency of a transmitter for determining the on/off cycle of image data, which is transmitted from a printer control part, at every page. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control system for a tandem cut paper laser beam printer.

  An example of the operation of a conventional tandem-connected cut paper laser beam printer is shown in FIGS. 3 is a block diagram showing a tandem connection of a cut sheet laser beam printer, FIG. 4 is a connection block diagram of a client PC, a printer control unit, and a laser control unit in a printing mechanism unit, and FIG. 5 is a conventional printing mechanism unit I in a printer control unit. FIG. 6 is a schematic block diagram of the / F section, and FIG. 6 is a timing chart of conventional sheet feeding speed control in the printing mechanism section.

  The printing mechanism of the cut paper laser printer includes a paper hopper 15, a drum 5, a developing device 14 that attaches toner to the drum, and a laser that receives image dot data transmitted from the printer control unit 1 and transmits it to the laser unit. The controller 17, the laser unit 12, the polygon mirror 11 that scans the laser beam in the horizontal direction, the reflection mirror 13 that irradiates the drum with the laser beam reflected from the polygon mirror, and the developing device 10 to the drum 5. The transfer unit 8 is configured to transfer the adhered toner onto the paper, and the fixing unit 6 applies heat and pressure to fix the toner transferred onto the paper. Further, in order to control the paper running and the transmission timing of the image dot data from the printer control unit 1, the top sensor 10 for detecting the top edge of the paper and the paper arrival time from the top sensor 10 to the transfer unit 8 are finely adjusted. And a skew sensor 9 provided for the purpose.

  As shown in FIG. 3, the tandem-cut cut paper laser beam printer is configured by arranging printing mechanism portions 2 of cut paper laser beam printers having substantially the same configuration except for the paper hopper 14 described above. The printer control unit 1 includes an operator panel 20 for an operator to check the status of the printer and set various modes. The printer control unit 1 is connected to a client PC via a network and analyzes and edits a print job transmitted from each client PC to print a printing mechanism. A drawing process is executed on the image dot data to be printed in one copy. Further, when the drawing process is executed on the image dot data, the printing mechanism unit is divided into image dot data for printing by the front printing mechanism unit 2a and image dot data for printing by the rear printing mechanism unit 2b. Image dot data is transmitted to each laser controller. At this time, the transfer timing of the image dot data to the printing mechanism unit of the printer control unit 1 is controlled and transferred so that the front-to-back relationship of pages to be printed by the front printing mechanism unit 2a and the rear printing mechanism unit 2b is not distorted. The The actual transfer timing is that when the paper picked from the paper hopper 15 by the paper pick command which is a command transmitted from the printer control device 1 reaches the top sensor 10, the paper has reached the top end of the paper from the printing mechanism. Is reported to the printer control unit 1 as a print sequence signal. Based on the report timing, the number of horizontal motive signals transmitted from the printing mechanism unit is counted to control the timing at which the toner is transferred from the paper and drum 5 by the transfer unit 8, and image dot data is sent to the laser control unit 17. Is synchronized with a horizontal synchronization signal transmitted from the printing mechanism unit, and is transmitted at a cycle of CLK14a having a frequency that is uniquely determined by the printing speed of the printing mechanism unit. At this time, also in the printing mechanism section, as shown in FIG. 6, the time until the picked paper passes through the top sensor 10 and reaches the skew sensor 9 through the register roller 7 is observed. As a result, the paper is defined. 6, the arrival time is adjusted in the period (mn) with respect to the distance m from the skew sensor 9 to the transfer device 8 shown in FIG. 6 to adjust the sheet conveyance speed. Done. Thus, the original sheet conveyance speed is restored at a point n before the transfer unit 8 and toner transfer from the drum to the sheet is executed in the transfer unit. The paper that has been printed and fixed by the front printing mechanism is conveyed to the rear printing mechanism as it is, and thereafter the image dot data to be printed by the rear printing mechanism is printed and fixed by the same operation and discharged to the tray 16. Is done.

  When spot color printing is executed, the printer control unit 1 executes color division processing on a page for a portion printed by the front printing mechanism unit 2a and a portion printed by the rear printing mechanism unit 2b. After the color division processing is completed, a paper pick instruction is issued in the same manner as described above, and the color-divided image dot data is transmitted to the front / rear printing mechanism at the same timing as described above, and printing is executed. The

  As described above, the color division processing within the page is executed by the printer control unit 1, and the color dot image dot data is transmitted to the front printing mechanism unit 2 a and the rear printing mechanism unit 2 b to execute spot color printing.

  In the conventional tandem cut paper laser beam printer, when spot color printing is executed as described above, paper shrinkage occurs due to the toner fixing process of the fixing device 6a executed at the time of printing by the front printing mechanism unit 2a. In this state, the color printing is performed in the rear printing mechanism 2b without taking into account the paper contraction, so that there is a positional deviation with respect to the “normal printing result” that should be printed as shown in FIG. A printing position misalignment as shown in “Printing Result When Occurred” occurred. In addition, since the actual print position deviation has various ratios of contraction in both vertical and horizontal directions depending on the size, characteristics, and environment of the paper, there is a possibility that the print result changes every time printing is performed.

  The tandem-connected cut paper laser beam printer that realizes spot colors by connecting the printing mechanisms of two conventional cut paper printers in tandem and having different color toners in each printing mechanism is capable of printing one color. Since the toner is fixed to the paper every time it is executed, the paper is shrunk when passing through the thermal compression fixing, and when the second color printing is executed, the amount of image dot data takes into account the paper shrinkage. As a result, there is a problem in that a printing position shift occurs.

  An object of the present invention is to improve printing position accuracy in response to paper contraction that occurs independently in the vertical and horizontal directions even in spot color printing with a tandem cut paper laser beam printer without adjusting the amount of image dot data. For the purpose.

  The purpose of the present invention is to detect the printing position shift in the spot color caused by the shrinkage of the paper by passing through the fixing unit for each printing of each page, and the front cut paper laser beam printer and the rear cut paper laser beam printer are independent of each other. The fine adjustment of the paper feed speed when transferring the toner from the paper drum to the paper by the amount of contraction in both the vertical and horizontal directions of the paper and the fine adjustment of the frequency of Hasshinki that determines the on / off cycle of the image data transmitted from the printer controller. This is accomplished by executing page by page.

  According to the present invention, since the reduction rate of image dot data can be selected independently for independent reduction in the vertical and horizontal directions of the paper, it is possible to improve the printing position accuracy corresponding to all paper sizes and directions. Can do.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a schematic block diagram of the printing mechanism internal I / F unit in the print control unit according to the present invention, and FIG. 2 is a timing diagram of the control of the paper conveying unit in the printing mechanism unit.

  In FIG. 1 and FIG. 2, as for the laser scanning direction (horizontal or horizontal direction), as shown in FIG. 1, image dot data hashing connected to the printing mechanism control unit 3 in the printer control unit 1 is replaced with a conventional printer. In addition to the frequency having a frequency uniquely determined by the printing speed, for example, n hashes are provided for 0.1% shrinkage units of the paper so that the hash can be selected in accordance with the shrinkage. As for the paper feeding direction, a conventional paper running control method is used as shown in FIG. The sheet transported at the original sheet transport speed CLK0 is observed at the point of the skew sensor 9, the sheet travel time from the top sensor 10, and the distance to the transfer unit 8 at the sheet transport speed CLK1 due to the delay / speed of arrival time. It travels a distance (mn) obtained by subtracting n minutes from m, and the arrival time from the top sensor 10 to the transfer device 8 is adjusted. Next, when printing reduction is required at the point of the distance n to the transfer unit 8, the sheet is transferred to the sheet transfer speed CLK 2 corresponding to the reduction amount, the sheet is transferred, and toner transfer is executed at the point of the transfer unit 8. . When the trailing edge of the sheet passes the transfer unit 8, the sheet traveling speed is returned to the original CLK0.

  The selection of the image dot data hashing and the selection of the sheet running speed CLK2 at the transfer point where the toner is transferred from the drum to the sheet operate according to the value selected by the operator from the operator panel. The selection of how much reduced printing the operator should make is selected by the operator according to the result of the test printing for print position adjustment before printing the actual job. Reflecting the reduction amount in each paper feed (vertical) direction and scan (horizontal or horizontal) direction set by the operator in actual printing is executed as follows.

  The paper feed direction is transferred to the printing mechanism unit together with the pick command at the timing of issuing the pick command sent from the printer control unit to the printing mechanism unit every time printing is actually performed. The scan direction corresponds to the adjustment for each page by selecting the hash used to be used at the reception timing from the top sensor transmitted from the printing mechanism section when printing is started.

  In addition, by applying the control corresponding to the paper contraction in the vertical and horizontal directions to both the front and rear printers, positional accuracy can be improved even in spot color printing with a tandem connection in a printer having a duplex printing mechanism. It becomes possible.

FIG. 2 is a schematic block diagram of a print mechanism unit I / F unit in a print control unit according to the present invention. FIG. 4 is a timing chart of control of the paper transport unit in the printing mechanism in the present invention. The block diagram of a tandem connection cut paper laser beam printer. FIG. 3 is a schematic connection diagram of a client PC, a printer control unit, and a laser control unit in a printing mechanism unit. FIG. 6 is a schematic block diagram of a conventional printer control unit internal printing mechanism I / F unit. FIG. 6 is a timing diagram of conventional printing mechanism internal sheet conveyance unit control. Explanatory drawing which shows the example of printing position shift.

Explanation of symbols

1 is a printer control unit, 2 is a printing mechanism unit, 3 is a printing mechanism unit control unit, 4 is a video clock hashing machine, 5 is a drum, 6 is a fixing device, 7 is a registration roller, 8 is a transfer device, and 9 is a skew sensor. 10 is a top sensor, 11 is a polygon mirror, 12 is a laser unit, 13 is a reflecting mirror, 14 is a developing device, 15 is a paper hopper, 16 is a paper tray, 17 is a laser control unit, 18 is a client PC, and 19 is tandem. Connection cut paper laser printer, 20 is an operator panel.

Claims (1)

Receives a print job transmitted from a host computer or a client computer on a network, executes a drawing process on image dot data for executing actual printing by the print mechanism unit, and executes one print job for each page. There is a printer control unit that performs data distribution to enable image dot data to be sent to an independent printing mechanism unit, an operator panel that is operated by an operator, and a printer control unit that performs actual printing. A laser control unit that receives image dot data transmitted at a predetermined period and performs transmission processing of the image dot data to the laser unit, and a mirror motor that turns on / off the laser beam by image dot data transmitted from the laser control unit A laser unit that irradiates an image on the drum with a mirror rotated by The image is transferred onto the drum unit, the developing unit for attaching toner to the laser irradiation unit on the drum, the transfer unit for transferring the toner from the drum to the paper, and the paper. Tandemly connect two printing mechanism units that consist of a fixing unit that applies heat and pressure to fix the toner, and perform black printing in the front printing mechanism unit and color printing in the rear printing mechanism unit In the tandem cut paper laser beam printer that realizes spot color printing by using the cut paper laser beam on the front side, the printing position shift in the spot color caused by the shrinkage of the paper by passing through the fixing unit for each printing of each page. The printer and the rear cut paper laser beam printer are each independently fed from the paper drum to the paper by the contraction amount of the paper in both the vertical and horizontal directions. Tandem-connected cut paper laser beam printer, wherein fine adjustment of the paper feed speed when transferring the image and fine adjustment of the frequency of the Haskinki for determining the on / off cycle of the image data transmitted from the printer control unit is executed for each page Control method.

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