JP2007152555A - Recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recorder having a large printer sheet-feeding control system using a roll sheet in which degradation of performance caused by variation in load occurring in the way of driving due to sagging or rotation of the roll sheet and different every time is eliminated. <P>SOLUTION: The recorder comprises a section for recording on a recording material, a means for conveying the recording material to the recording section while pinching by means of a sheet feed roller and a pinch roller, a means for driving the sheet feed roller, a means for controlling the drive means, a plurality of speed detection means, a load estimation means, and a parameter regulation means for regulating the control means wherein the state of a load is estimated by the load estimation means and control parameters are switched depending on the load. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a recording apparatus equipped with a sheet conveying apparatus that conveys a sheet equipped in an image forming apparatus such as a copying machine, a laser beam printer, and a facsimile to a recording position.

  2. Description of the Related Art Conventionally, recording devices equipped in printers, copiers, facsimiles, or the like, or recording devices used as output devices for multifunction devices and workstations including computers, word processors, and the like, are based on image information such as paper and plastic thin plates (for example, An image (including characters and symbols) is recorded on a recording material such as an OHP sheet. This recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a thermal transfer type, a laser beam type, etc., depending on the recording method of the recording means used.

  Among the above recording apparatuses, in the serial scan type recording apparatus in which the recording head performs main scanning in the direction crossing the conveyance direction (sub-scanning direction) of the recording material, after setting the recording material at a predetermined recording position, An image (including characters and symbols) is recorded by a recording means (recording head) mounted on a carriage that moves (main scans) along the recording material, and a predetermined amount of paper is recorded after recording for one line is completed. By repeating the operation of feeding (sub-scanning) and then recording the next row of images (main scanning), the image is recorded in the desired range of the recording material.

  Nowadays, DC motors and rotary encoders are increasingly used as driving means for the recording medium conveyance mechanism. From the viewpoint of noise reduction, the effect can be expected by adopting a DC motor, but from the viewpoint of increasing the accuracy of recording medium conveyance, more advanced position control is required in addition to mechanical accuracy. In order to realize highly accurate conveyance, it is necessary to set the control gain to an appropriate value.

  As a conveying method, friction conveyance by a roller is often used. In the friction conveyance, a recording medium is sandwiched between rollers, and tension is applied by the roller to carry the conveyance. In such a recording apparatus, the elongation of the recording medium due to changes in the material and environment of the sheet, especially in the recording material conveying mechanism of a large-sized printer mainly using roll paper, the difference in roll paper winding diameter or roll paper There are a variety of recording materials and various recording materials such as the occurrence of sagging due to inertia.

  It is difficult to determine optimal control parameters under various recording material conditions. For example, if the control gain is too large, the control system oscillates or an overshoot occurs and the conveyance accuracy deteriorates. Oscillation can cause device destruction.

  If the control gain is too small, it may take time to reach the target value, or the target value may not be reached, and the conveyance accuracy may be deteriorated.

  Due to these factors, there is a difference between the predetermined amount to be conveyed and the conveyance amount of the recording material, and there is a problem that the image quality is remarkably deteriorated.

In order to solve this problem, Patent Document 1 provides a pair of speed detection means upstream and downstream of the image forming unit, calculates a correction amount for misregistration from the conveyance speed, and performs correction to prevent image quality deterioration. .
JP 2002-236404 A

  However, when the prior art of Patent Document 1 is applied to a serial scan type recording apparatus, an action of correcting the feed amount occurs, so that the main scan and the sub scan are not continuously performed, and the time until the printing is completed. Longer and lowering productivity.

  Accordingly, the present invention has been made to solve the above-described problems of the prior art, and a recording unit for recording on a recording material, and the recording material is sandwiched between a paper feed roller and a pinch roller and conveyed to the recording unit. It comprises a conveying means, a driving means for driving the paper feed roller, a control means for controlling the driving means, a plurality of speed detecting means, a load estimating means, and a parameter adjusting means for adjusting the control means. And

  Highly accurate conveyance is realized by estimating the state of the load by the load estimating means and switching the control parameter according to the load.

  According to the present invention, there are various types of recording materials and various recording materials such as differences in material and size, in addition, differences in the winding diameter of roll paper and occurrence of slack due to the inertia of the roll paper. Even when it is, stable conveyance can be realized and productivity can be provided without lowering.

  A schematic operation of the recording apparatus according to the present invention will be described with reference to FIG.

  A transport unit composed of a paper feed roller 1 and a pinch roller 2 for transporting a recording material 14 which is a roll paper, a driving means 3 for driving the paper feed roller 2, and a rotation speed of the paper feed roller 2 are detected. 1 speed detection means, a second speed detection means for detecting the moving speed of the recording material 14, and the like.

  The driving unit 3 rotates the paper feed roller 2 via a transmission mechanism (not shown). The recording material 14 is conveyed by a predetermined amount while being sandwiched between the paper feed roller 1 and the pinch roller 2. Thereafter, recording is performed while a recording head (not shown) moves in a direction perpendicular to the recording material conveyance direction. By repeating the above operation, an image is recorded in a desired range of the recording material.

  The PI compensation means 6 and the control compensation means 9 are a predetermined amount of paper feed determined in advance, a paper feed roller speed observed by the first speed detection means 4, and a recording material obtained by the transport amount conversion means. Are compared and the compensation calculation is performed. Thereafter, the drive circuit 10 amplifies appropriately and drives the drive means 3.

  The PI compensator 6 and the control compensator 9 are often PI compensators that are generally used, but are not limited to PI compensators.

  The first speed detecting means is arranged near the paper feed roller, and the second detecting means is arranged in a place where no slack of the recording material 14 occurs.

  The load estimation means estimates the load state from the detection speed of the first speed detection means and the detection speed of the second speed detection means, and operates the parameter switching means according to the load. The parameter switching means decreases the control parameter when the load is light, and increases the control parameter when the load is heavy. The control parameter is either or both of the proportional gain term 7 and the integral gain term 8. Moreover, you may change the control parameter of the control compensation means 9 as needed.

  The behavior of the load estimation means will be described with reference to the flowchart of FIG.

  When the detection speed of the first speed detection means is V1 and the detection speed of the second speed detection means is V2, V1 and V2 are compared (S2), and no slack occurs when driving with V1 = V2. Therefore, it is determined that there is no load fluctuation (S3).

  When V1 <V2, sagging occurs, so it is determined that the load is light (S4).

  When V1> V2, the sagging is confirmed (S5), and if sagging exists, it is determined that the load is light (S4).

  If there is no slack, it is determined that the load is heavy (S6).

  FIG. 3 shows the effect of the present invention. It can be seen that the target value is quickly reached without causing overshoot or failure to reach the target value depending on the state of the load. Since the target value is set, it is not necessary to correct the transport amount.

Block diagram of recording apparatus in the present invention Flow chart showing the behavior of the load estimation means Graph showing the effect of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Paper feed roller 2 Pinch roller 3 Drive means 4 1st speed detection means,
5 Transportation amount conversion means 6 PI compensator 7 Proportional gain term 8 Integral gain term,
9 control compensator 10 drive circuit 11 load estimation means 12 parameter switching means,
13 Second detection means 14 Recording material

Claims (2)

  A recording unit that records on a recording material, a conveyance unit that sandwiches the recording material between a paper feeding roller and a pinch roller and conveys the recording material to the recording unit, a driving unit that drives the paper feeding roller, and a control unit that controls the driving unit A recording apparatus comprising: a control means; a plurality of speed detection means; a load estimation means; and a parameter adjustment means for adjusting the control means.   The recording apparatus according to claim 1, wherein the plurality of speed detecting units detect the speeds of the paper feed roller and the recording material.

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