JP2010069782A - Image recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image recorder configured to eliminate an error of a recording position when recording an image using a sheet type recording paper and also prevent an image from being damaged during conveyance of the recording paper after recording. <P>SOLUTION: The image recorder includes a recording head for recording an image by ejecting ink, and an adsorption platen having a recording medium supporting surface extending in a direction orthogonal to a recording medium conveying direction oppositely to the recording head, and is characterized by including a pair of nip rollers provided on an upstream side of the adsorption platen, and an adsorption conveying belt provided on a downstream side of the adsorption platen. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technical field of an image recording apparatus such as an ink jet printer. More specifically, the present invention can be suitably used for borderless printing while transporting a recording medium as a single row or a plurality of rows, particularly in a sheet form. The present invention relates to an image recording apparatus that eliminates a recording position error at the time of image recording using recording paper, and prevents an image from being damaged during conveyance after recording.

  In recent years, there has been an increasing demand for borderless printing using an inkjet printer. This is because the ink jet printer is basically an easy process close to the dry process, and with the development of the ink jet printing technology etc., the quality (image quality) of the image formed is significantly improved. This is because the image quality of prints using salt photographic materials is approaching and the difference is almost gone.

In response, business-use inkjet printers are also being used. In business-use inkjet printers, roll paper is cut to a length corresponding to image formation before printing, and printed in sheet form, from the standpoint of recording material costs and prevention of loss due to intermediate cuts between images. (That is, inkjet printing) is preferable.
However, when performing borderless printing on a sheet-like recording material with an ink jet printer, there are many problems as will be described later. Currently, after an image is continuously formed on roll paper, this is cut for each image. The method to do is common.

  The basic configuration of an ink jet printer is that a recording head having a plurality of nozzle arrays that eject ink toward the recording medium on a surface facing the recording surface of the recording medium, and the recording medium supported from below. A platen that maintains a distance between the head and the recording medium, a unit that controls scanning and ink ejection of the recording head, a unit that controls conveyance (corresponding to sub-scanning) of the recording medium, and the like. .

Incidentally, in recent years, there has been a strong demand for higher image quality of images recorded using an ink jet printer. This is due to the fact that the field of use has come to be widely used commercially from the so-called hobby use for personal use.
The problem at this time is that the image quality deteriorates due to a recording position shift caused by a recording paper conveyance error that occurs during recording. There is also a problem of scratches caused by contact with the recording surface that occurs when the recording paper after recording is conveyed.

  The former causes a slight shift in the conveyance speed between the plurality of roller pairs, suction conveyance means, and the like when conveying the sheet-like recording medium by combining a plurality of roller pairs, adsorption conveyance means, and the like. As a result, a conveyance error of the recording medium occurs, and accordingly, the recording position by the ink jet also shifts. This problem is caused by a shift in the conveyance speed between a plurality of conveyance units (roller pairs or suction conveyance units) used when conveying the recording medium.

Regarding this problem, for example, a technique disclosed in Patent Document 1 is known.
This technique records an image by optical scanning while sandwiching and conveying a conventional roll-shaped (long) recording medium between two pairs of rollers disposed upstream and downstream of the recording position. In such a case, the problem that the flatness of the recording medium cannot be maintained due to the difference in rotational speed between the two roller pairs (specifically, the roller pair on the downstream side rotates slightly at a low speed). In this case, the recording medium is urged so as to be pulled away from the upstream roller pair by the downstream roller pair to maintain the flatness of the recording medium.

However, when a sheet-like recording medium is used in this technique, the recording medium is transported only by the downstream roller pair rotating slightly faster after the recording medium is removed from the upstream roller pair. However, the recording density changes from the middle, resulting in a problem that the quality of the recorded image is deteriorated.
This problem occurs in exactly the same way regardless of whether the image recording method is an optical (photographic) image recording method or an inkjet image recording method.

In order to cope with such a problem, the technique disclosed in Patent Document 1 controls the speed of the recording medium at the timing at which the rear end of the recording medium is separated from the upstream roller pair. The speed control based on the transport speed is changed to the speed control based on the transport speed of the downstream roller pair.
As a result, the transport speed of the upstream roller pair and the transport speed of the downstream roller pair do not fluctuate as described above, so that the trailing edge of the recording medium passes through the upstream roller pair. It is said that the image quality of the image recorded on the recording medium is suppressed from decreasing before and after.

JP 2007-260938 A

  However, this technique also has the following problems. That is, in this technique, while the recording medium having a predetermined length is sandwiched between both the upstream-side transport roller pair and the downstream-side transport roller pair, the recording medium is pulled downstream by the downstream-side transport roller pair. An image is recorded on the recording medium. When the trailing edge of the recording medium passes through the upstream conveying roller pair and the recording medium is no longer sandwiched between the upstream conveying roller pair, the recording medium is thereafter sandwiched and conveyed by the downstream conveying roller pair. Will be.

However, in the ink jet printer, if the nip roller, which is the conveying means in the preceding stage of the recording unit, is used as the recording medium conveying means in the subsequent stage of the recording unit, it has an unfavorable influence on the production of a high-quality print on the undried image surface. Effect.
That is, when an undried image surface touches the nip roller, ink movement occurs or a scratch or the like of the roller is transferred to the image surface.

  As a countermeasure against this, there is a method in which conveyance is performed by a point contact nip roller called several star wheels instead of a line contact at a recording paper width like a nip roller. However, even in this configuration, minute marks (dot holes) are formed on the image surface of the recording medium. Therefore, in order to convey the image surface without scratching or the like, it is preferable to use a means for conveying the recording paper by contacting only the back surface of the recording medium.

  Actually, in an ink jet printer that uses a sheet-like recording medium, a device that includes intermittent conveying means that performs intermittent sub-scanning at a specified pitch from the start of recording on the feed roller upstream of the recording unit is used. In this case, after the trailing end of the sheet-like recording medium is removed from the feed roller, the recording paper is conveyed by contacting only the back surface of the recording medium on the downstream side of the recording unit. Move on to the back side only.

  In the ink jet printer configured in this way, continuous transfer (conveyance without speed fluctuation) can be realized by taking over the recording paper conveying means before and after the recording unit without interruption in time. Since vibration occurs at the time of transfer of control of conveyance drive, high-precision conveyance to the recording unit is impaired, and high-quality printing is affected.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an improved image recording apparatus which has solved the problems based on the prior art.
More specifically, it can be suitably used for borderless printing while transporting the recording medium as a single row or a plurality of rows, and in particular eliminates a recording position error at the time of image recording using a sheet-like recording paper, An object of the present invention is to provide an image recording apparatus in which an image is not damaged during conveyance after recording.

  In order to achieve the above object, an image recording apparatus according to the present invention includes a recording head that performs image recording by discharging ink, and a recording that extends in a direction orthogonal to the recording medium conveyance direction so as to face the recording head. An image recording apparatus having an adsorption platen having a medium support surface, comprising: a pair of nip rollers provided upstream of the adsorption platen; and an adsorption conveyance belt provided downstream of the adsorption platen. .

  Further, in the image recording apparatus according to the present invention, the nip roller pair provided upstream of the suction platen is configured to be able to release the nip of the recording medium, and the recording target is recorded when the recording head performs recording. It is preferable that the recording medium is intermittently conveyed, and the surface thereof is subjected to a non-slip treatment.

  In the image recording apparatus according to the present invention, the suction conveyance belt provided downstream of the suction platen receives the recording medium recorded by the recording head, and receives the recording medium in synchronization with the nip roller pair. It is preferable to carry out intermittent conveyance or continuous conveyance.

  In the image recording apparatus according to the present invention, the switching of the driving force between the pair of nip rollers provided upstream of the suction platen and the suction conveyance belt provided downstream of the suction platen is performed by the recording head. It is preferable that the performed recording medium is started when conveyance by the suction conveyance belt is started and the conveyance force by the adsorption conveyance belt is ensured, and at the same time, the nip roller pair releases the nip of the recording medium. .

  In the image recording apparatus according to the present invention, the time from when the conveyance of the recording medium recorded by the recording head is started by the adsorption conveyance belt to when the conveyance force by the adsorption conveyance belt is secured is It is preferable that the time from when the conveyance by the suction conveyance belt is started to when the nip of the nip roller pair provided upstream of the suction platen is released is equal.

  According to the present invention, it can be suitably used when performing borderless printing while transporting the recording medium as a single row or a plurality of rows, in particular, eliminating a recording position error at the time of image recording using a sheet-like recording paper, There is a remarkable effect that it is possible to realize an image recording apparatus in which an image is not damaged during conveyance after recording.

  Hereinafter, the image recording apparatus of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

  FIG. 1 shows a conceptual diagram of an example of an ink jet printer using the image recording apparatus of the present invention.

As shown in FIG. 1, the image recording apparatus 10 includes a recording medium loading unit 12, a recording medium supply unit 14, an image recording unit 16, a drying unit 18, and a discharge unit 20.
In addition, the image recording apparatus 10 includes a control unit 24 that performs control and management of operations of the entire image recording apparatus 10, management of operation history, and the like.

The recording medium loading unit 12 includes a roll-shaped recording medium loading unit 32 and a recording sheet cassette 36. The roll-shaped recording medium loading unit 32 is arranged at the lower stage in the apparatus, and the recording sheet cassette 36 is arranged above it.
As shown in FIG. 1, the roll-shaped recording medium loading unit 32 is provided below the image recording apparatus 10, and includes a magazine 38, a flange 40, flange rotation rollers 42 and 44, and a feed roller 46. Have. The flange 40, the flange rotation rollers 42 and 44, and the feed roller 46 are disposed in the magazine 38.
The magazine 38 is loaded with a roll-shaped recording medium 48 as a printing medium. The magazine 38 has a structure that can be pulled out from the apparatus housing, and the roll-shaped recording medium 48 to be loaded can be exchanged.

The roll-shaped recording medium 48 is configured to be wound around a cylindrical core member (not shown) so that the outer peripheral surface side becomes an image recording surface. The length and width dimension of the roll-shaped recording medium 48 are not particularly limited. For example, a long recording medium having a width in the range of 89 mm to 210 mm can be used. In addition, a recording medium of any surface type can be used as the recording medium. For example, a recording paper having a glossy surface or a matte surface, and a recording paper having a thermoplastic resin on the substrate surface can be used.
When a roll-shaped recording medium having a narrow width is used, a plurality of roll-shaped recording media may be loaded in the magazine 38 side by side in the paper surface depth direction (rotation axis direction). By loading a plurality of roll-shaped recording media, it is possible to record an image while conveying a narrow recording medium in multiple rows of two or more rows, and it is possible to increase printing efficiency.

  The flange 40 includes a core member that is rotatably disposed in the magazine 38 and a flange portion having an outer diameter larger than the maximum outer diameter of the roll-shaped recording medium 48 at both ends of the core member. A roll-shaped recording medium 48 is wound around the core member of the flange 40, and the width direction of the end portion of the roll-shaped recording medium 48 is regulated by the flange portions at both ends and guided in the width direction.

The flange rotation rollers 42 and 44 are arranged in parallel with each other at a predetermined distance in the horizontal direction at a position below the flange 40, and are in contact with the outer periphery of the flange portion of the flange 40. Further, the respective flange rotation rollers 42 and 44 are connected to a rotation driving unit (not shown). By rotating the flange rotation rollers 42 and 44 in the forward direction or the reverse direction by the rotation drive unit, the flange 40 can be rotated, and the roll-shaped recording medium 48 can be sent out or taken up.
The feed roller 46 sandwiches the drawn roll-shaped recording medium 48 under the control of the control unit 24 and conveys it to the recording medium supply unit 14 described later.

The recording sheet cassette 36 is a storage member for stacking and storing recording sheets 50 cut in advance to a predetermined size, and is configured to be detachable from the image recording apparatus 10.
The recording sheets 50 are stacked in the recording sheet cassette 36 so that the image recording surface is positioned on the lower side. The recording sheets 50 in the recording sheet cassette 36 are fed one by one by a paper feed roller 52 disposed above the recording sheet cassette 36 and sent out to a recording medium supply unit 14 described later.

  The recording medium supply unit 14 is provided to convey the long recording medium or recording sheet sent out from the recording medium loading unit 12 to the image recording unit 16. The recording medium supply unit 14 includes a cutter 54, a back printing unit 56, a width guide 58, a turn roller 62, and eight feed rollers 64, 66, 68, 70, 72, 74, 76, 78.

The turn roller 62 changes the direction of the long roll-shaped recording medium 48 fed substantially horizontally from the roll-shaped recording medium loading unit 32, and directs the roll-shaped recording medium 48 toward the back printing unit 56 positioned above. It is a roller for carrying.
Further, the feed roller 64 is provided on the downstream side in the transport direction of the turn roller 62 in the transport path of the roll-shaped recording medium 48, and transports the roll-shaped recording medium 48 drawn from the recording medium loading unit 12. Further, the feed roller 66 is disposed on the downstream side of the feed roller 64 in the conveying direction, separated from the feed roller 64 by a predetermined distance. The feed roller 68 is disposed at a predetermined distance from the feed roller 66 on the downstream side in the transport direction of the feed roller 66.
The cutter 54 is disposed between the feed roller 64 and the feed roller 66 in the conveyance path of the roll-shaped recording medium 48, and cuts the roll-shaped recording medium 48 into a recording medium having a predetermined length. Further, the cutter 54 cuts the roll-shaped recording medium 48 when a predetermined process is completed or when a long recording medium is replaced in the middle.

  The loop forming portion 69 is provided between the feed roller 66 and the feed roller 68. The loop forming unit 69 forms a recording medium loop in the loop forming unit 69 by releasing a transport guide (not shown) provided in a direction perpendicular to the transport surface. Here, when the recording medium is cut by the cutter 54, since it is necessary to temporarily stop the conveyance of the recording medium, the feed roller 64 intermittently conveys the recording medium, but a loop forming unit 69 is provided. As a result, it is possible to prevent a load that affects the cutting operation of the recording medium by the cutter 54 from being applied to the conveyance path downstream from the loop forming unit 69, and the back printing unit 56 to be described later performs stable back printing. be able to.

  The feed rollers 70 and 72 convey the recording sheet 50 sent out from the recording sheet cassette 36 toward the back printing unit 56.

The back printing unit 56 records an image of a recording sheet 50 (hereinafter simply referred to as “recording medium P”) supplied from the roll-shaped recording medium 48 or the feed roller 72 cut from the feed roller 68 to a predetermined length. This is a printing device for recording predetermined back printing information on the opposite side of the surface, and is provided downstream of the feed roller 72 in the transport direction.
The back printing unit 56 is configured using, for example, a dot impact printer or an ink jet printer. Further, the back print information is exemplified by an image file name, image correction information, and the like.
A feed roller 74 is disposed on the upstream side in the transport direction from the back printing unit 56, and a feed roller 76 is disposed on the downstream side in the transport direction.

The feed roller 78 conveys the recording medium P on which the reverse print is recorded by the reverse print unit 56 toward the width guide 58.
The width guide 58 is disposed on the upstream side of the feed roller 80 of the image recording unit 16 described in detail later, and adjusts the position in the width direction of the recording medium P entering the image recording unit 16. The width guide 58 adjusts the position and orientation of the recording medium P in the width direction so that the recording medium P is conveyed to a predetermined position of the image recording unit 16 (so that no positional deviation occurs).

Next, the image recording unit 16 will be described in detail.
Here, FIG. 2 is a front view schematically showing a schematic configuration around the image recording unit 16 of the image recording apparatus 10, and FIG. 3A is a cross-sectional view taken along the line IIIA-IIIA in FIG. FIG. 3B is a cross-sectional view taken along line IIIB-IIIB in FIG. 4A to 4C are schematic side views showing a recording medium conveyance state in the image recording unit 16 during recording.
The image recording unit 16 includes a feed roller 80, an ink discharge unit 82, a platen 84, a suction conveyance belt 86, and a mask mechanism 90.
The feed roller 80 is a roller disposed on the downstream side of the width guide 58, and conveys the recording medium P whose position in the width direction is regulated by the width guide 58 to the platen 84. Here, the feed roller 80 has a lift-up mechanism related to the upper roller in the figure, and sandwiches the recording medium P as shown in FIGS. 4A to 4C according to an instruction from the control unit 24. / Can be switched to nipping release.

  The ink ejection unit 82 is a serial type image recording unit that forms an image on a recording medium while reciprocating in the width direction of the recording medium (hereinafter also referred to as a main scanning direction). A recording head unit 100 that discharges ink, a head scanning mechanism 102 that moves the recording head unit 100 in the sub-scanning direction, and a position detection sensor 104.

As shown in FIGS. 2 and 3, the recording head unit 100 is disposed to face the recording medium P, and drops ink droplets onto the recording medium P conveyed by the feed roller 80 to form an image. Form.
The recording head unit 100 has four types of inkjet heads that eject ink droplets corresponding to each color of cyan (C), magenta (M), yellow (Y), and black (K). These four types of inkjet heads are arranged side by side in the main scanning direction.
In addition, each inkjet head has a plurality of ejection openings that eject ink on the surface facing the recording medium P. In addition, as a method for driving the inkjet head (that is, a method for ejecting ink droplets), a piezo method that uses vibration by a piezo element (piezoelectric element), a thermal method that uses pressure of bubbles generated in ink by a heating element, Any electrostatic driving method using the electric charge applied to the ink droplets can be used.

The head scanning mechanism 102 includes a head support 106 that supports the recording head unit 100, shafts 108 a and 108 b that are inserted through the head support 106 and arranged in a direction in which the axis is parallel to the main scanning direction, and the head support. And a drive unit 110 for moving 106 along the shaft 108.
The head support 106 is a plate-like member, and supports a surface perpendicular to the recording medium P of the recording head unit 100 and parallel to the sub-scanning direction.
The shaft 108a is a rod-shaped member having a thread groove formed therein, and is screwed to the head support 106, and the shaft 108b is a rod-shaped member not formed with a thread groove, and is connected to the head support 106 in the main scanning direction. It is movably inserted in. The shaft 108a and the shaft 108b are arranged in parallel with a predetermined distance therebetween.

The drive unit 110 is a rotation mechanism that rotates the shaft 108a, and moves the head support 106 that is screwed to the shaft 108a in the main scanning direction by rotating the shaft 108a.
In this way, the head scanning mechanism 102 causes the drive unit 110 to rotate the shaft 108a and move the head support 106 in the main scanning direction along the shafts 108a and 108b, thereby moving the recording head unit 100 in the main scanning direction. Move back and forth.
The head operating mechanism for moving the recording head unit 100 in the main scanning direction is not limited to the method using screw transmission as in the present embodiment. For example, a method using a belt or a pulley, a method using an electrostatic force, or the like. A method used in a serial scan type ink jet printer can be used.

The position detection sensor 104 is fixed to the head support 106 adjacent to the end of the recording head unit 100 in the main scanning direction. The position detection sensor 104 detects whether or not the recording medium P is present at an opposing position (on a platen 84 described later). The position detection sensor 104 can also detect the end of the recording medium P by detecting the presence or absence of the recording medium P.
The ink discharge means 82 is basically configured as described above.

Next, the platen 84 is arranged on the downstream side of the feed roller 80 in the conveyance direction of the recording medium P so as to face the area where the recording head unit 100 is scanned, and the recording conveyed from the feed roller 80 is performed. The medium P is supported at a predetermined position.
In addition, a plurality of suction holes 85 are formed in the surface of the platen 84 in contact with the recording medium P so as to be arranged at regular intervals in the transport direction.
By supporting the recording medium P by the platen 84, the distance between the recording medium P and the recording head unit 100 can be made constant, and the landing accuracy of the ink droplets ejected from the recording head unit 100 is further increased. be able to.

The fan 88 is disposed on the surface opposite to the surface of the platen 84 that is in contact with the recording medium P, and generates a flow of air in a downward direction from the platen 84 positioned above the platen 84. The number of fans 88 may be one or more.
By generating an air flow by the fan 88, the recording medium P in contact with the platen 84 can be sucked to the platen 84 side from the suction holes 85 formed in the platen 84, and the recording medium P is sucked into the platen 84. Can be absorbed.
Note that if the suction force of the suction hole 85 formed in the platen 84 is too strong, it may be difficult to transport the recording medium P. Therefore, the suction force of the suction hole 85 formed in the platen 84 depends on the feed roller. It is desirable that the suction force is such that the recording medium P can be transported by 80 or a suction transport belt 86 described later.

  The suction conveyance belt 86 is disposed on the downstream side of the platen 84 in the conveyance direction of the recording medium P, and has a function of conveying the recording medium P fed from the feed roller 80 and passed through the platen 84 further downstream. is there. As a material constituting the suction conveyance belt 86, a material having a small thermal shrinkage, for example, stainless steel 304 is preferable.

  Next, the mask mechanism 90 includes an upstream side mask 120 and a downstream side respectively disposed on four sides of an area where an image is formed on the recording medium P by the ink ejection unit 82 (hereinafter simply referred to as “image forming area”). Mask 122 and two end masks 124, 126, mask supports 130, 132 for supporting the end masks 124, 126, a shaft 134 screwed into the mask supports 130, 132, and a shaft for rotating the shaft 134, respectively. And a rotation mechanism 136.

The upstream mask 120 is a plate-like member having a long side in the direction parallel to the main scanning direction, and between the platen 84 and the recording head unit 100 in the direction perpendicular to the conveyance path of the recording medium P, and The platen 84 is fixed at a position spaced apart from the surface with which the recording medium P contacts. Further, the upstream mask 120 is fixed at a position in contact with the side on the upstream side in the conveyance direction of the image forming area (that is, the edge of the area) in the sub-scanning direction.
A recess is formed on the surface of the upstream mask 120 on the recording head unit 100 side, and an absorbing member 138 made of a material that absorbs ink is placed in the recess. The absorbing member 138 is disposed up to the edge in contact with the image forming area of the upstream mask 120.
As the absorbing member 138, various substances that absorb ink, such as sponge, can be used.

The downstream mask 122 is a plate-like member having a long side in the direction parallel to the main scanning direction, and is the same as the upstream mask 120 on a plane parallel to the upstream mask 120 and parallel to the platen 84. It is fixed on a plane. That is, the downstream mask 122 is also fixed at a position spaced apart from the surface of the platen 84 on which the recording medium P contacts with a predetermined distance. Further, the downstream mask 122 is fixed at a position in contact with the side (that is, the edge of the region) on the downstream side in the conveyance direction of the image forming region in the sub-scanning direction.
A recess is also formed on the surface of the downstream mask 122 on the recording head unit 100 side, and the absorbing member 140 is placed in the recess. The absorbing member 140 is also arranged up to the edge in contact with the image forming area.

The end mask 124 and the end mask 126 are plate-like members, are arranged between the upstream mask 120 and the downstream mask 122, and are slidable with the upstream mask 120, the downstream mask 122, and the platen 84. In contact. Further, the end mask 124 and the end mask 126 are arranged to face each other with a line connecting the midpoint of the long side of the upstream mask 120 and the midpoint of the long side of the downstream mask 122 as a symmetric line. Yes.
Further, the end mask 124 and the end mask 126 also have recesses formed on the surface on the recording head unit 100 side, and the absorbing members 142 and 144 are placed in the recesses.
The absorbing member 142 is disposed up to the edge of the end mask 124 on the center side of the platen 84, and the absorbing member 144 is disposed up to the edge of the end mask 126 on the center side of the platen 84.

The mask support 130 is an L-shaped plate member, one end of which is joined to the surface of the end mask 124 opposite to the surface facing the recording medium P, and the other end is in the vicinity. It is screwed with a shaft 134 described later. Further, the mask support 130 is such that the straight portion joined to the end mask 124 is parallel to the surface of the platen 84, and the straight portion joined to the shaft 134 is perpendicular to the surface of the platen 84. It is arranged in the direction.
The mask support 132 is symmetrical to the mask support 130 with a line connecting the midpoint of the long side of the upstream mask 120 and the midpoint of the long side of the downstream mask 122 as a symmetric line. The end is joined to the surface of the end mask 126 opposite to the surface facing the recording medium P, and the vicinity of the other end is screwed to a shaft 134 described later.

The shaft 134 is disposed at a position farther from the platen 84 than the fan 88 in a direction parallel to the main scanning direction. The shaft 134 is formed with a thread groove, and the thread groove is formed so that the spiral direction is reversed at the center (that is, the clockwise spiral becomes a counterclockwise spiral).
The shaft rotation mechanism 136 supports the shaft 134 at a predetermined position and rotates the shaft 134 in an arbitrary direction.

The mask mechanism 90 is configured as described above. By rotating the shaft 134 by the shaft rotating mechanism 136, the mask supports 130 and 132 screwed to the shaft 134 are moved in the main scanning direction, and the mask is rotated. The end mask 124 supported by the support 130 and the end mask 126 supported by the mask support 132 are moved in the main scanning direction.
Here, since the direction of the spiral of the shaft 134 is reversed at the center, the end mask 124 and the end mask 126 are made symmetrical with respect to the symmetry axis (that is, the center reference) by rotating the shaft 134. And the distance between the end mask 124 and the end mask 126 can be adjusted.
Thereby, the mask mechanism 90 moves on the end mask 124, the end mask 126 and the platen 84 by adjusting the distance between the end mask 124 and the end mask 126 according to the width of the recording medium P. The end of the recording medium P to be contacted can be brought into contact.
As a result, the four sides of the platen 84 in the region where ink droplets are ejected by the recording head unit 100 can be surrounded by the upstream mask 120, the downstream mask 122, the end mask 124 and the end mask 126.

Next, the drying unit 18 will be described with reference to FIG.
The drying unit 18 includes a drying fan 92 disposed to face the suction conveyance belt 86 (the surface on which the recording medium P is placed), and ink on the recording medium on which an image is recorded by the image recording unit 16. Dry. The drying fan 92 blows air onto the image forming surface of the conveyed recording medium to promote ink drying.

Here, in this embodiment, the ink is dried by the drying fan. However, a heater for promoting the drying of the ink may be used instead of the drying fan, and the drying fan is used for further promoting the drying. And a heater may be used in combination.
In addition, it is preferable to provide a drying unit because the ink of the image recorded on the recording medium P can be dried in a shorter time. However, the drying state of the ink differs depending on the recording medium and the type of ink used. Therefore, for example, when using a recording medium or ink that dries ink immediately, the drying unit 18 may not be provided.

The discharge unit 20 includes a feed roller 94 and an orthogonal conveyance belt 96. The feed roller 94 is provided on the downstream side of the suction conveyance belt 86 in the conveyance direction, and discharges the print conveyed by the adsorption conveyance belt 86 to the outside from a discharge port (not shown) of the housing of the image recording apparatus. The orthogonal conveyance belt 96 can convey the print discharged from the discharge port in a direction (front side) perpendicular to the paper surface of FIG.
The prints conveyed by the orthogonal conveyance belt 96 are accumulated on an accumulation tray (not shown). The stacking tray may be composed of a circulating sorter that sorts prints for each order.
The image recording apparatus 10 is basically configured as described above.

  Next, the operation of the image recording apparatus 10 will be described to describe the image recording apparatus of the present invention in more detail. Hereinafter, a case where an image is recorded (drawn) on the roll-shaped recording medium 48 will be described. Even when an image is recorded on the recording sheet 50, the image is basically recorded in the same process except that there is no operation of cutting the recording medium into a predetermined length.

First, the image recording unit 16 rotates the shaft 134 by the shaft rotation mechanism 136 of the mask mechanism 90 according to the width of the recording medium P to be used, and the distance (interval) between the end mask 124 and the end mask 126 is increased. The end mask 124 and the end mask 126 are moved so as to have the width of the recording medium P.
Next, the flange rotation rollers 42 and 44 and the feed roller 46 inside the magazine 38 are rotated, and the roll-shaped recording medium 48 is pulled out from the magazine 38.
The drawn roll-shaped recording medium 48 is redirected by the turn roller 62 and conveyed by the feed rollers 64 and 66.
When the drawn roll recording medium 48 reaches the feed roller 68, the feed roller 68 is not rotated, and a loop of the roll recording medium 48 is formed between the feed roller 66 and the feed roller 68. . Then, when the length of the roll-shaped recording medium 48 from the feed roller 68 to the cutter 54 becomes a certain distance, the roll-shaped recording medium 48 is cut by the cutter 54 to become a recording medium P having a predetermined length.

  The recording medium P cut by the cutter 54 is conveyed by feed rollers 68, 74, 76 and printed on one side (that is, the back side) of the recording medium P when passing through a position facing the back printing unit 56. Information is recorded.

  Thereafter, the recording medium P is conveyed by the feed rollers 76 and 78, the position and orientation in the width direction are adjusted by the width guide 58, and then conveyed to the feed roller 80 of the image recording unit 16.

The recording medium P transported to the image recording unit 16 is transported further, passes between the platen 84 and the upstream mask 120, and is in a state where both ends in the width direction are in contact with the end masks 124 and 126.
The recording medium P is further transported, and when the leading edge reaches the downstream mask 122, ink ejection by the recording head unit 100 is started. Whether the recording medium P has reached the downstream mask 122 is detected by detecting the leading edge of the recording medium P by the position detection sensor 104 and then calculating from the transported distance, the recording is performed on the downstream mask 122. A sensor for detecting the medium P may be arranged.

The image recording unit 16 ejects ink droplets from the recording head unit 100 to the recording medium P while moving the recording head unit 100 of the ink ejection means 82 in the main scanning direction, and each time the recording head unit 100 reciprocates once. Or every time the recording medium P moves in one direction, the recording medium P is conveyed in the conveyance direction (hereinafter also referred to as “sub-scanning direction”) by the feed roller 80 or the suction conveyance belt 86 by the length of the drawing area by the recording head unit 100. Intermittently. By repeating such an operation, an image can be recorded on the recording medium P.
Here, when forming an image on the recording medium P, the recording head unit 100 ejects ink to the outside of both ends of the recording medium P so that the image is recorded up to the edge (end) of the recording medium P. Perform borderless printing. Note that the ink ejected to the outside of both ends of the recording medium P lands on the absorbing members 142 and 144 on the end masks 124 and 126 that are in contact with the end of the recording medium P.
Further, the ink ejecting means 82 detects the end of the recording medium P by the position detection sensor 104, thereby reliably recording an image up to the end of the recording medium P.
Further, at the time of image recording, the recording medium P is sucked by the platen 84 by the fan 88.

  The recording medium P on which an image is formed by the image recording unit 16 is further transported by the suction transport belt 86. When transported by the suction transport belt 86, drying of the ink is promoted by the drying unit 18, and the image recorded on the recording medium P is dried.

Here, a conveyance control method for the recording medium P in the image recording unit 16, which is a characteristic operation of the image recording apparatus 10 according to the present invention, will be described.
As described above, the recording medium P is sent to the image recording unit 16 from the left side in the drawing. In this situation, the recording medium P is nipped by the feed roller 80 and conveyed while being attracted onto the platen 84 by the fan 88. This conveyance is intermittently sent in the sub-scanning direction by the length of the drawing area by the recording head unit 100 every time the recording head unit 100 reciprocates once or moves in one direction. It is as follows.

When the recording medium P is further conveyed and the trailing end reaches the sensor roller 80 a of the feed roller 80, a sensor (not shown) detects this and sends a signal to the control unit 24. Upon receiving this signal, the control unit 24 releases the nip of the recording medium P on the feed roller 80 by the nip roller 80 b of the feed roller 80, and causes the subsequent conveyance of the recording medium P only to the suction conveyance belt 86.
In this way, by substantially preventing a plurality of transport mechanisms from being simultaneously involved in transport of the recording medium P, “sway” (along the transport direction) on the transport of the recording medium P in the image recording unit 16. (Vibration in the front-rear direction in the direction) can be prevented, and the recorded image can have high image quality.

  That is, the feed roller 80 is provided with a small-diameter roller 80a on the left side (inlet side) of the main roller in the drawing, and a small-diameter pressing roller 80b on the upper side in the drawing. The small-diameter pressing roller 80b has a mechanism that lifts up the main roller. In response to an instruction from the control unit 24, FIGS. In addition, as shown in the flowchart shown in FIG. 5, the recording medium P can be switched between nipping and nipping.

The operation shown in FIGS. 4A to 4C will be described below.
FIG. 4A shows that the recording medium P has been fed into the image recording unit 16, and at this stage, the recording medium P is a small-diameter roller 80a having functions of a main roller and a sensor in the feed roller 80. Similarly, the small-diameter pressing roller 80b is pressed against the main roller with a predetermined pressure, and functions as a nip roller.

FIG. 4B shows a moment (step 150) when the recording medium P is further conveyed and its rear end is separated from the small-diameter roller 80a having the sensor function of the feed roller 80. The recording medium emitted at this time is shown in FIG. Based on the “rear end passage signal” of P, the nip of the small-diameter pressing roller 80b of the feed roller 80 is released (step 152).
At this stage, the recording medium P is transported only by the suction transport belt 86. Note that this conveyance also intermittently sends out the recording medium P.

FIG. 4C shows a moment (step 154) in which the recording medium P is further conveyed and the leading edge of the recording medium P ′ to be fed next is detected by the small-diameter roller 80a having a sensor function in the feed roller 80. Yes. Then, based on the leading edge detection signal of the recording medium P issued at this time, a state where the nip of the small-diameter pressing roller 80b of the feed roller 80 has recovered (step 156) is shown.
Thereafter, the three-stage operation is performed in a circulating manner, and the “recording” of the recording medium P in the image recording unit 16 is prevented from being shaken, and the recorded image has a high image quality. it can.

  The conveyance control method of the recording medium P in the image recording unit 16 described above is not limited to the above-described embodiment, and includes various types such as a feed roller 80 and a short endless belt wound around the outer side by a predetermined angle. It is possible to make changes.

(0050)
Thereafter, the recording medium P is discharged by a feed roller 94 and is stacked on a predetermined stacking tray by an orthogonal conveying belt 96 in a direction perpendicular to the paper surface (not shown).
The image recording apparatus 10 records an image on the recording medium P as described above.

  In the above embodiment, an example is shown in which image recording is performed by conveying the recording medium in a single row. There is a remarkable effect that it is possible to realize an image recording apparatus that eliminates a recording position error at the time of image recording using recording paper and that does not cause scratches on the image during conveyance after recording.

  The above embodiment shows an example of the present invention, and the present invention is not limited to the above embodiment, and various modifications and improvements are made without departing from the spirit of the present invention. Needless to say, it may be.

1 is a front view showing a schematic configuration of an embodiment of an image recording apparatus of the present invention. It is a top view which shows typically the peripheral part of the image recording part of the image recording apparatus shown in FIG. (A) is the IIIA-IIIA sectional view taken on the line of FIG. 2, (B) is the IIIB-IIIB sectional view taken on the line of FIG. FIGS. 3A to 3C are schematic side views illustrating details of a conveyance system of an image recording unit of the image recording apparatus of the embodiment. 6 is a flowchart illustrating details of conveyance control of a recording medium around an image recording unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Image recording device 12 Recording medium loading part 14 Recording medium supply part 16 Image recording part 18 Drying part 20 Ejection part 24 Control part 32 Roll recording medium loading part 36 Recording sheet cassette 38 Magazine 40 Flange 46 Feed roller 48 Roll recording medium 50 Recording Sheet 52 Paper Feed Roller 54 Cutter 56 Back Printing Unit 58 Width Guide 64, 66, 68, 70, 72, 74, 76, 78, 80 Feed Roller 80a Sensor Roller 80b Nip Roller 82 Ink Ejecting Means 84 Platen 86 Adsorption Transport Belt 88 Fan 90 Mask mechanism 92 Drying fan 94 Feed roller 96 Orthogonal conveying belt 100 Recording head unit 102 Head scanning mechanism 104 Position detection sensor 106 Head support 108 Shaft 110 Drive unit 120 Upstream side Disk 122 downstream mask 124 ends the mask 130 mask support 134 shaft 136 shaft rotation mechanism 138,140 absorbing member 150, 152 process steps

Claims (5)

A recording head for recording an image by discharging ink;
An image recording apparatus having an adsorption platen having a recording medium support surface extending in a direction orthogonal to the recording medium conveyance direction facing the recording head,
An image recording apparatus comprising: a pair of nip rollers provided upstream of the suction platen; and a suction conveyance belt provided downstream of the suction platen.   The nip roller pair provided upstream of the suction platen is configured to be able to release the nip of the recording medium, and intermittently conveys the recording medium to be recorded when recording with the recording head, The image recording apparatus according to claim 1, wherein a non-slip treatment is applied to the surface.   2. The suction conveyance belt provided downstream of the suction platen receives a recording medium recorded by the recording head, and intermittently conveys or continuously conveys the recording medium in synchronization with the nip roller pair. The image recording apparatus described in 1.   The switching of the driving force between the pair of nip rollers provided upstream of the suction platen and the suction conveyance belt provided downstream of the suction platen is such that the recording medium recorded by the recording head is conveyed by the suction conveyance belt. The image recording apparatus according to claim 2, wherein the image recording apparatus is started when the conveyance force by the suction conveyance belt is ensured, and at the same time, the nip roller pair releases the nip of the recording medium.   The time from the start of conveyance of the recording medium recorded by the recording head by the suction conveyance belt to the securing of the conveyance force by the adsorption conveyance belt is from the start of conveyance by the adsorption conveyance belt. The image recording apparatus according to claim 2, which is equal to a time until the nip of a pair of nip rollers provided upstream of the suction platen is released.

Images