JP2019043689A - Printing device - Google Patents

Abstract

To reduce paper sheets to which paper wrinkles are formed.SOLUTION: A printing device comprises: an inkjet head 130 for printing a paper sheet: a pre-resist conveyance part 390 provided with two rollers 392s, 392t at a predetermined interval L1 and conveying the paper sheet on a conveyance path by rotating the rollers 392s, 392t; and a resist part provided with a roller 352d arranged in a position including a range overlapping the predetermined interval L1 formed by the rollers 392s, 392t, on downstream side in a conveyance direction of the rollers 392s, 392t, with a rotational axis direction perpendicular to a conveyance direction, and transferring to the ink jet head 130 by rotating the roller 352d, a sheet butted upon conveyance by the pre-resist conveyance part 390. A length L2 of the roller 352d in the rotational axis direction is equal to or longer than the predetermined interval L1, and a length L3 between outside ends of the two rollers 392s, 392t is longer than the length L2 of the roller 352d in the rotational axis direction.SELECTED DRAWING: Figure 2

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a printing apparatus that appropriately corrects skewing without forming a paper sheet.

  In the printing apparatus, the sheet fed from the sheet feeding table is conveyed along the conveyance path by the conveyance roller. The sheet conveyed by the conveyance roller is abutted against the registration roller, and the registration roller rotates at a predetermined timing to correct the skewed sheet and convey the sheet to the printing unit.

  Here, the conveyance roller and the registration roller have an axial shaft whose rotation axis direction is a direction orthogonal to the conveyance direction of the sheet, and a pressure roller fixed to the axial shaft and pressing the sheet. The pressure roller is partially provided in the rotation axis direction to reduce damage to the paper sheet or the like.

  For example, Patent Document 1 discloses a technique related to a registration roller in which a plurality of pressing rollers (left roller portion, center roller portion and right roller portion) are axially arrayed and fixed on one shaft shaft.

Unexamined-Japanese-Patent No. 2007-238216

  Here, the conveying roller for conveying the sheet to the registration roller may also be configured by a plurality of divided pressing rollers in the same manner as the registration roller described in Patent Document 1.

  With such a configuration, slack of the sheet may be formed along the transport direction between the pressure rollers of the transport roller. If the sheet is abutted against a registration roller provided with a pressure roller at a position overlapping the pressure roller of the conveyance roller in the conveyance direction in a state where the slack is formed, the skew correction may not be properly performed.

  Further, when the pressing roller positions of the conveying roller and the registration roller are simply provided in the direction of the rotational axis so as to be alternately arranged, the slack formed between the pressing rollers of the conveying roller is pressed by the pressing roller of the registration roller. There was a case that a paper sheet was formed.

  The present invention has been made in view of the above problems, and provides a printing apparatus capable of reducing the occurrence of wrinkles on a sheet passing through a registration roller even if the sheet has slack in the transport direction formed by the conveyance roller. The purpose is

In order to achieve the above object, a first feature of the printing apparatus according to the present invention is
Printing means for printing on paper;
First transport means provided with two first rollers at predetermined intervals symmetrically with respect to a center line parallel to the transport direction of the paper, and transporting the paper on the transport path by rotation of the first roller;
A direction perpendicular to the conveyance direction is a rotation axis direction at a position including a range overlapping the predetermined interval formed by the two first rollers, which is downstream in the conveyance direction of the first roller 2 rollers are provided, and second conveying means for conveying the sheet, which has been conveyed to the first conveying means and abutted to the printing means by rotating the second roller;
The length of the second roller in the rotational axis direction is equal to or greater than the predetermined distance, and the length between the outer end portions of the two first rollers is longer than the length of the second roller in the rotational axis. is there.

  According to the feature of the printing apparatus according to the present invention, it is possible to reduce the number of sheets on which the sheet crease is formed.

It is a figure showing an outline of an ink jet printing device concerning one embodiment of the present invention. It is the top view which showed the positional relationship of the pre-registration conveyance roller and the registration roller with which the inkjet printing apparatus which is one Embodiment of this invention is equipped. It is the perspective view which showed the structure of the guide plate with which the ink jet printer concerning one embodiment of the present invention is provided. FIG. 6 is a view showing a state in which a sheet is conveyed by the pre-registration conveyance unit included in the inkjet printing apparatus according to the embodiment of the present invention. (A) is the side view seen from the conveyance near side direction of the conveyance part before registration, (b) is a front view of the conveyance part before registration. FIG. 5 is a view showing a state in which a sheet is conveyed by a registration unit provided in the inkjet printing apparatus according to the embodiment of the present invention. (A) is the side view seen from the conveyance near side direction of a resist part, (b) is a front view of a resist part.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts or components are denoted by the same or equivalent reference numerals throughout the drawings. However, it should be noted that the drawings are schematic and different from real ones. Moreover, it is a matter of course that parts having different dimensional relationships and ratios among the drawings are included.

  Further, the embodiment shown below is an example of an apparatus etc. for embodying the technical idea of the present invention, and the technical idea of the present invention includes the material, shape, structure, and the like of each component. The arrangement etc. are not specified to the following. Various changes can be added to the technical idea of the present invention within the scope of the claims.

<Configuration of inkjet printing apparatus>
In one embodiment of the present invention, black or color ink is ejected from a nozzle of an ink jet head on a sheet transported on a transport path based on print data such as image information and text information to print an image or text. An inkjet printing apparatus for printing will be described as an example.

  FIG. 1 is a schematic view of an ink jet printing apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the inkjet printing apparatus 100 receives an operation signal for requesting various operations such as printing start based on the control unit 10 including a controller board or the like on which a CPU etc. is disposed, and the user's operation. The control panel 10 is provided with an operation panel 50 and the like.

  Further, the ink jet printing apparatus 100 has a side paper feed stand 320 exposed to the outside of the side surface of the case and a plurality of paper feed trays (330 a, 330 b) provided inside the case as a paper feeding mechanism for supplying the paper P. , 330c, 330d).

  Then, the sheet P fed one by one from the sheet feeding mechanism of one of the side sheet feeding tray 320 and the sheet feeding tray 330 is fed by a driving mechanism such as a roller or the like to the sheet feeding conveyance path FR (black in FIG. It is conveyed along the thick line) and led to the resist unit 350. Here, the registration unit 350 is provided to correct the skew feeding of the sheet P, and includes a registration roller 351.

  The registration roller 351 is mechanically connected to a drive motor (not shown) serving as a drive source, and includes a drive roller 352 that is rotationally driven by the drive motor and a driven roller 353 that is rotated by pressure contact with the drive roller 352. Have.

  The fed sheet P is temporarily stopped at the registration unit 350 for skew feeding correction, and the drive roller 352 and the driven roller 353 are brought into pressure contact with each other at a predetermined timing to be rotated, thereby being conveyed toward the printing mechanism.

  Before the registration unit 350 in the transport direction, there is a junction where the transport path of the fed sheet P and the path through which the sheet P having one surface printed is transported are merged. Based on this junction point, the path on the side of the paper feed mechanism is referred to as a paper feed conveyance path FR, and the other path is referred to as a circulation conveyance path CR.

  A plurality of inkjet heads 130 are provided downstream of the registration unit 350 on the circulation conveyance path CR in the conveyance direction, and C (cyan), M (magenta), and Y (yellow) are sequentially provided from the registration unit 350. , K (black) are arranged in order. The color order is not limited in this order, and each user may set the optimum order as appropriate. The paper P is printed in units of lines by the ink ejected from the respective inkjet heads 130 while being conveyed at a speed determined by the printing conditions by an annular conveyance belt 360 provided on the opposing surface of the inkjet heads 130.

  A suction fan 370 is provided inside the conveyance belt 360. A large number of air holes are formed on the surface of the conveyance belt 360, and the sheet P is attracted to the conveyance belt 360 and conveyed by the suction force generated by the rotation of the suction fan 370.

  The printed sheet P is further transported in the housing by a drive mechanism such as a circulation transport roller 310 provided at a plurality of locations in the circulation transport path CR.

  Then, in the case of single-sided printing in which printing is performed only on one side of the sheet P, the sheet P is guided as it is to the sheet discharge outlet 340 and discharged. Is loaded on the bottom. The sheet discharge tray 345 has a tray shape protruding from the housing and has a certain thickness. The sheet discharge tray 345 is inclined, and a wall formed at the lower position of the inclination allows the sheet P which is discharged from the sheet discharge port 340 to be slipped along the inclination to be naturally arranged and overlap. ing.

  In the case of double-sided printing in which printing is performed on both sides of the sheet P, the front side (the first side to be printed is called “front side” and the next side to be printed is called “back side”) In addition, the inside of the case is transported. For this reason, the inkjet printing apparatus 100 includes a switching mechanism 380 for switching the conveyance path for back surface printing. The sheet P which has not been guided to the sheet discharge outlet 340 by the switching mechanism 380 is pulled into the switchback path SR, performs switchback, and reverses the front and back with respect to the transport path.

  Then, the pre-registration conveyance unit 390 provided on the circulation conveyance path CR guides the sheet P to the registration unit 350 again.

  The pre-registration conveyance unit 390 includes a pre-registration conveyance roller 391 and a guide plate 395.

  The pre-registration conveyance roller 391 is mechanically connected to a drive motor (not shown) serving as a drive source, and is driven by a drive motor to drive the drive roller 392 and driven by the pressure roller 392. The drive roller 392 and the driven roller 393 are brought into pressure contact with each other to rotate, whereby the sheet P is conveyed and abuts against the registration roller 351 of the registration unit 350.

  The guide plate 395 is disposed on the drive roller 392 side of the pre-registration conveyance roller 391, and guides the sheet P from the pre-registration conveyance roller 391 to the registration unit 350 by rotational driving of the drive roller 392. The structure of the guide plate 395 will be described later.

  The sheet P abutted against the registration roller 351 again by the pre-registration conveyance roller 391 while being guided by the guide plate 395 is temporarily stopped for skew correction. Thereafter, the sheet is conveyed to the ink jet head 130 by the registration roller 351 at a predetermined timing, and printing on the back surface is performed according to the same procedure as the front surface. Printing on the back side is performed, and the sheet P on which images have been formed on both sides is again transported inside the housing by a drive mechanism such as a circulation transport roller 310 provided at a plurality of locations in the circulation transport path CR.

  In the embodiment of the present invention, when the sheet is conveyed by the pre-registration conveyance roller 391 and the registration roller 351, skew feeding is appropriately corrected without forming a sheet wrinkle.

  FIG. 2 is a plan view showing the positional relationship between the pre-registration conveyance roller 391 and the registration roller 351 included in the ink jet printing apparatus 100 according to an embodiment of the present invention.

  As shown in FIG. 2, the inkjet printing apparatus 100 includes a drive roller 392 of the pre-registration conveyance roller 391 of the pre-registration conveyance unit 390 and a drive roller 352 of the registration roller 351 of the registration unit 350.

  The driving roller 392 of the pre-registration conveying roller 391 has a cylindrical shape made of rubber or resin, and ceramic particles for anti-slip are formed on the outer peripheral surface with minute irregularities (a ceramic coating is applied) ) Rollers 392s and 392t, and these rollers are fixed to an axial shaft 392r provided with a direction perpendicular to the conveyance direction of the sheet P as a rotation axis. The rollers 392s and 392t are provided at predetermined intervals L1 symmetrically with respect to a center line R parallel to the sheet P conveyance direction.

  The length in the rotational axis direction of the rollers 392s and 392t is the same, and the sum of the distance L1 and the length in the rotational axis direction of the rollers 392s and 392t is the distance from the outer end of the roller 392s to the outer end of the roller 392t It becomes L3. Incidentally, the driven roller 393 which is in pressure contact with the drive roller 392 also has a roller at the same position.

  If the drive roller 392 has an integral roller continuous in the rotational axis direction, if slack is formed on the sheet P, there is no escape place for eliminating the slack, and the slack is pressed by the continuous integral roller And the paper sheet is formed.

  On the other hand, the drive roller 392 is not a continuous roller in the rotational axis direction, but has rollers 392s and 392t partially provided in the rotational axis direction. Slack can be released to L1. As a result, since the formed slack is not pressed by the rollers 392s and 392t, it is possible to prevent the formation of the sheet wrinkle due to the pressing of the drive roller 392 and the driven roller 393.

  The driving roller 352 of the resist roller 351 has a cylindrical shape made of rubber or resin, and minute irregularities are formed by ceramic particles on the outer peripheral surface to prevent slip (ie, ceramic coating is applied) ) Has a roller 352b, a roller 352c, a roller 352d, a roller 352e and a roller 352f, and these rollers are fixed to an axial shaft 352a provided with a direction orthogonal to the conveyance direction of the sheet P as a rotation axis .

  Similar to the pre-registration conveyance roller 391, the registration roller 351 of the registration unit 350 is also provided with rollers 352b, 352c, 352d, 352e, and 352f partially in the rotation axis direction in order to prevent the formation of a sheet crease. . The driven roller 353 in pressure contact with the driving roller 352 also has a roller at the same position.

  The roller 352d provided at the central portion in the rotational axis direction is a position corresponding to the distance L1, that is, the downstream side of the rollers 392s and 392t in the conveyance direction, and overlaps the distance L1 formed by the rollers 392s and 392t. It is provided at the position including the range. Further, the length L2 of the roller 352d is equal to or greater than the interval L1 between the rollers 392s and 392t. As a result, the area passing the interval L1 between the rollers 392s and 392t of the sheet P is pressed by the roller 352d of the registration roller 351.

  As described above, since the roller 352d is provided at a position corresponding to the interval L1 between the rollers 392s and 392t, even when slack of the sheet P along the transport direction is formed between the rollers 392s and 392t, the sheet P Since the slack is eliminated by the roller 352 d by the conveyance of the sheet P, the skew feeding correction of the sheet P appropriately conveyed can be performed.

  However, since a sheet crease is formed when pressed by the roller 352 d in a state in which the slack is formed, the slack is taken as the sheet P until the slack formed on the transported sheet P reaches the roller 352 d. Need to escape to the outside of the

  Therefore, the distance L3 to the outer end of the rollers 392s and 392t is longer than the length L2 of the roller 352d in the rotational axis direction. In addition, the pressure (pressing force) pressed by the roller 352d provided at the central portion to the sheet P is larger than the pressure (pressing force) pressed by the rollers 352b, 352c, 352e, and 352f provided on both sides. Provided in

  As a result, the sheet P is mainly pressed and conveyed by the three rollers of the rollers 392s and 392t and the roller 352d.

  Since the sheet P is pressed by three rollers, tension is applied in the plane formed by the three rollers. Therefore, even when the slack S1 along the transport direction is formed on the sheet P, the slack S1 is released in the width direction of the sheet P like the slack S2 between the pre-registration transport roller 391 and the registration roller 351. As a result, it is possible to eliminate the slack and prevent the formation of a sheet crease.

  Furthermore, in the pre-registration conveyance unit 390, a guide plate 395 for guiding the sheet P conveyed by the pre-registration conveyance roller 391 to the registration unit 350 is provided.

  FIG. 3 is a perspective view showing the structure of the guide plate 395 provided in the ink jet printing apparatus 100 according to an embodiment of the present invention.

  As shown in FIG. 3, the guide plate 395 is provided with two roller arrangement holes 395j and 395k.

  The positions of the two roller arrangement holes 395j and 395k are provided corresponding to the positions of the rollers 392s and 392t of the drive roller 392 of the pre-registration conveyance roller 391. Therefore, the rollers 392s and 392t protruding from the roller arrangement holes 395j and 395k contact the sheet P while rotating, and press-contact with the driven roller 393 to convey the sheet P in the A direction (conveying direction).

  Guide rails 395a to 395f are provided on the surface for guiding the sheet P so as to open in the width direction of the sheet P toward the downstream side in the A direction (conveyance direction) of the sheet P.

  As a result, even when the sheet P is slackened along the transport direction, the slack is more easily released in the width direction of the sheet P, and thus the slack is easily eliminated.

  The guide plate 395 provided with the guide rails 395 a to 395 f is disposed on the drive roller 392 side of the pre-registration conveyance roller 391, but may be provided on the driven roller 393 side. It may be provided on both the driven roller 393 side.

  FIG. 4 is a view showing a state in which the sheet P is conveyed by the pre-registration conveyance unit 390 provided in the inkjet printing apparatus 100 according to the embodiment of the present invention. (A) is the side view seen from the conveyance near side direction of conveyance part 390 before registration, and (b) is a front view of conveyance part 390 before registration.

  As shown in FIGS. 4A and 4B, when the sheet P is conveyed by the pre-registration conveyance roller 391, a slack S may be formed at an interval L1 between the rollers 392s and 392t.

  Also in this case, since the formed slack S is not pressed by the rollers 392s and 392t, it is possible to prevent the formation of the sheet wrinkle due to the pressing of the driving roller 392 and the driven roller 393.

  FIG. 5 is a view showing a state in which the sheet P is conveyed by the registration unit 350 provided in the inkjet printing apparatus 100 according to an embodiment of the present invention. (A) is the side view seen from the conveyance near side direction of the resist part 350, (b) is a front view of the resist part 350. FIG.

  As shown in FIGS. 5A and 5B, the sheet P pressed by the drive roller 392 and the driven roller 393 by the drive roller 392 of the pre-registration conveyance roller 391 and the driven roller 393 being in pressure contact with each other and rotated. And is abutted against the registration roller 351 of the registration unit 350.

  As described above, the length L2 of the roller 352d of the registration roller 351 is set to be equal to or larger than the interval L1 between the rollers 392s and 392t of the pre-registration conveyance roller 391.

  Therefore, even when a slack of the sheet P in the transport direction is formed between the rollers 392s and 392t, the slack is eliminated by the roller 352d by the transport of the sheet P.

  Further, the distance L3 to the outer end of the rollers 392s and 392t of the pre-registration conveyance roller 391 is set to be longer than the length L2 of the registration roller 351 in the rotational axis direction of the roller 352d.

  Therefore, since it is pressed by the three rollers of the rollers 392s and 392t and the roller 352d, tension is applied in the plane formed by the three rollers. Therefore, even when the sheet P is slackened along the transport direction, the slack can be released in the width direction of the sheet P. Therefore, the slack can be eliminated and the formation of the sheet wrinkle can be prevented.

  The sheet P, which has been abutted, is temporarily stopped in a state where the slack is formed along the rotation axis of the registration roller 351, and the drive roller 352 and the driven roller 353 contact each other at a predetermined timing and rotate. Row corrected.

  Thus, skew feeding can be appropriately corrected without forming a sheet wrinkle on the sheet P which has passed through the registration roller.

  Further, guide rails 395a to 395f are provided on the surface of the guide plate 395 for guiding the sheet P so as to open in the width direction of the sheet P toward the downstream side in the conveyance direction A of the sheet P.

  As a result, even when the sheet P is slackened along the transport direction, the slack is more easily released in the width direction of the sheet P, and thus the slack is easily eliminated.

  Further, the pressing force by the roller 352d provided at the center of the registration roller 351 against the sheet P is set to be larger than the pressing force by the rollers 352b, 352c, 352e, and 352f provided on both sides.

  As a result, the sheet P is mainly pressed and conveyed by the three rollers of the rollers 392s and 392t and the roller 352d.

  Although the pre-registration conveyance unit 390 is described as an example in the embodiment of the present invention, any conveyance unit that conveys the sheet P to the registration unit 350 is applicable.

  In the embodiment of the present invention, the inkjet type inkjet printing apparatus 100 performing printing on a line basis has been described as an example, but the present invention is not limited to this, and serial inkjet type, laser type, stencil printing type, etc. It may be a printing device.

(Supplementary note)
The present application discloses the following invention.

(Supplementary Note 1)
Printing means for printing on paper;
First transport means provided with two first rollers at predetermined intervals symmetrically with respect to a center line parallel to the transport direction of the paper, and transporting the paper on the transport path by rotation of the first roller;
A direction perpendicular to the conveyance direction is a rotation axis direction at a position including a range overlapping the predetermined interval formed by the two first rollers, which is downstream in the conveyance direction of the first roller 2 rollers are provided, and second conveying means for conveying the sheet, which has been conveyed to the first conveying means and abutted to the printing means by rotating the second roller;
The length of the second roller in the rotational axis direction is equal to or greater than the predetermined interval, and the length between the outer ends of the two first rollers is longer than the length of the second roller in the rotational axis. Characterized printing device.

(Supplementary Note 2)
A guide plate for guiding the sheet conveyed by the first conveyance means to the second conveyance means;
The printing apparatus according to (Appendix 1), wherein the guide plate has a guide rail formed on the surface for guiding the sheet so as to open in the width direction of the sheet toward the downstream side in the sheet conveyance direction.

(Supplementary Note 3)
The second conveying means further includes third rollers disposed on both sides in the rotational axis direction of the second roller,
The printing apparatus according to (Appendix 1) or (Appendix 2), wherein a pressing force by the second roller on the sheet is larger than a pressing force by the third roller.

(Supplementary Note 4)
Printing means for printing on paper;
First transport means provided with two first rollers at predetermined intervals symmetrically with respect to a center line parallel to the transport direction of the paper, and transporting the paper on the transport path by rotation of the first roller;
A direction perpendicular to the conveyance direction is a rotation axis direction at a position including a range overlapping the predetermined interval formed by the two first rollers, which is downstream in the conveyance direction of the first roller (2) second conveying means provided with two rollers, and conveying the sheet which has been conveyed and abutted against the first conveying means to the printing means by rotating the second roller;
And a guide plate for guiding the sheet conveyed by the first conveyance means to the second conveyance means.
The printing apparatus, wherein the guide plate has a guide rail formed on the surface for guiding the sheet so as to open in the width direction of the sheet toward the downstream side in the sheet conveyance direction.

100 inkjet printing apparatus 130 inkjet head (printing means)
310 circulation conveyance roller 320 side paper feed stand 330 paper feed tray 340 discharge outlet 345 paper discharge stand 350 registration unit (second conveyance means)
351 Registration Roller 352 Drive Roller 352a Shaft Shaft 352d Roller (Second Roller)
352b, 352c, 352e, 352f rollers (third roller)
353 Driven roller 390 Pre-registration conveyance section (first conveyance means)
391 Pre-registration conveying roller (conveying roller)
392 drive roller 392r shaft shaft 392s, 392t roller (first roller)
393 follower roller 395 guide plates 395a, 395b, 395c, 395d, 395e, 395f guide rails 395j, 395k roller arrangement holes

Claims (4)

Printing means for printing on paper;
First transport means provided with two first rollers at predetermined intervals symmetrically with respect to a center line parallel to the transport direction of the paper, and transporting the paper on the transport path by rotation of the first roller;
A direction perpendicular to the conveyance direction is a rotation axis direction at a position including a range overlapping the predetermined interval formed by the two first rollers, which is downstream in the conveyance direction of the first roller 2 rollers are provided, and second conveying means for conveying the sheet, which has been conveyed to the first conveying means and abutted to the printing means by rotating the second roller;
The length of the second roller in the rotational axis direction is equal to or greater than the predetermined interval, and the length between the outer ends of the two first rollers is longer than the length of the second roller in the rotational axis. Characterized printing device. A guide plate for guiding the sheet conveyed by the first conveyance means to the second conveyance means;
The printing apparatus according to claim 1, wherein the guide plate has a guide rail formed on the surface for guiding the sheet so as to open in the width direction of the sheet toward the downstream side in the sheet conveyance direction. The second conveying means further includes third rollers disposed on both sides in the rotational axis direction of the second roller,
The printing apparatus according to claim 1, wherein a pressing force of the second roller on the sheet is larger than a pressing force of the third roller. Printing means for printing on paper;
First transport means provided with two first rollers at predetermined intervals symmetrically with respect to a center line parallel to the transport direction of the paper, and transporting the paper on the transport path by rotation of the first roller;
A direction perpendicular to the conveyance direction is a rotation axis direction at a position including a range overlapping the predetermined interval formed by the two first rollers, which is downstream in the conveyance direction of the first roller (2) second conveying means provided with two rollers, and conveying the sheet which has been conveyed and abutted against the first conveying means to the printing means by rotating the second roller;
And a guide plate for guiding the sheet conveyed by the first conveyance means to the second conveyance means.
The printing apparatus, wherein the guide plate has a guide rail formed on the surface for guiding the sheet so as to open in the width direction of the sheet toward the downstream side in the sheet conveyance direction.

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