JP2001088375A - Apparatus and method for ink-jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly discharge ink adhering on a platen. SOLUTION: Platen ribs 61 as projections for holding a medium to be recorded to a proper recording position are set on a platen 60. Holes 62 are opened to both sides of a root part 63 of the platen rib 61 to be parallel to side faces of the platen rib 61. When ink adheres wrong to the platen 60, e.g. when an image of a larger breadth than a breadth of the medium to be recorded is printed wrong or in a like case, the ink is guided to the root part 63 by a gravity or a surface tension of the ink if the ink of some volume or more collects and is smoothly discharged from the holes 62 along the side faces of the platen rib 61.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus used as an output device of an information terminal such as a personal computer, a word processor and a facsimile.

[0002]

2. Description of the Related Art In a conventional ink jet recording apparatus which discharges ink and adheres to a recording medium to perform recording, the ink is discharged as a main component for determining a position where the ink adheres to the recording medium. A carriage on which the head is mounted, a head moving means for performing main scanning for moving the head together with the carriage on the recording medium in one direction, and scanning a recording position in that direction, and for transporting the recording medium It has a transport roller and a platen that supports the recording medium downstream of the transport roller and maintains the positional relationship between the print surface of the recording medium and the recording head with high accuracy when recording is performed. The recording operation is performed by the recording head being moved by the head moving means on the recording medium conveyed onto the platen by the conveying roller to perform main scanning, eject ink, and adhere the ink to the recording medium.

[0003]

In a conventional ink jet recording apparatus, various sizes of paper may be used as a recording medium, and it is confirmed that the size of the recorded image matches the size of the paper. In some cases, a paper width sensor to detect the width of the paper is provided for the purpose of doing so, but such a paper width sensor is not installed in order to simplify the recording device and reduce manufacturing costs. There are many.

Therefore, if an image having a width larger than the width of the paper is erroneously printed, ink adheres to the platen. In such a case, if left unattended for a long time without cleaning, the ink sticks to the platen, and there is a risk that paper may be caught on the stuck ink and transport failure may occur. It is necessary to clean the ink adhered to the surface.

Further, in the conventional ink jet recording apparatus, in order to discharge ink droplets from the recording head properly and to perform printing on the paper more accurately, the ink is discharged from the recording head immediately before the printing is started, and the ink is discharged. A preliminary ejection operation is generally performed in which new ink is introduced near the ejection port and the state of the ink in this portion is made appropriate. The preliminary ejection is performed to a position outside the maximum width of the sheet that can be transported by the apparatus, that is, a position outside the maximum printing range, so that the ink ejected by the preliminary ejection does not adhere to the recording medium or the platen. This is performed after moving the recording head in the main scanning direction.

In this preliminary ejection operation, even when printing is performed on a sheet having a small width, it is necessary to move the recording head to a position outside the maximum printing range, and accordingly, printing is performed on one sheet. Time will be long.

Accordingly, an object of the present invention is to provide an ink jet recording head which can easily remove the adhered ink even if the ink adheres to the platen by mistake. Another object of the present invention is to provide an ink jet recording head capable of performing preliminary ejection efficiently.

[0008]

In order to achieve the above object, an ink jet recording apparatus according to the present invention comprises a head for performing recording by discharging ink and attaching the ink to a recording medium, and a head for recording at a position where recording is to be performed. In an ink jet recording apparatus having a platen supporting a recording medium at a position facing the recording medium, the platen is formed so that the platen rib is a projection for guiding the recording medium and the side of the platen rib is along the side surface of the platen rib. Characterized by having a perforated hole.

According to this configuration, when ink adheres to the platen, for example, when an image having a width larger than the width of the paper is erroneously printed, an ink having a certain volume or more is deposited on the platen. When the ink accumulates, the ink adhering to the platen rib is guided by gravity to the base of the platen rib, and the ink adhering to the portion where the platen rib is not provided tends to collect due to surface tension. It is attracted to the ink attached near the root and is guided to this portion. In this way, the ink gathers at the base of the platen rib, is guided along the side surface of the platen rib to a hole formed along the side surface of the platen rib, and is smoothly discharged from this hole.

[0010] Further, there is provided a head moving means for moving the head to a position facing a desired recording position of the recording medium on the platen, and a recording medium of a plurality of sizes mainly used in the ink jet recording apparatus. Correspondingly,
By providing holes on the platen near the outside of the edge of the recording medium of each size with respect to the moving direction of the head, it is possible to correspond to the size of the recording medium to be recorded immediately before ink is ejected for recording. The head can be moved to a position facing the hole, and preliminary ejection can be performed, and the ejected ink can be ejected from this hole, and the moving distance of the head at the time of preliminary ejection can be shortened as compared with the related art.

[0011]

(Embodiment 1) FIG. 1 is a schematic view of an ink jet recording apparatus according to Embodiment 1 of the present invention. As shown in the drawing, in a print head 10 that performs printing by discharging ink, a nozzle row in which a plurality of nozzles that discharge ink are arranged at specified intervals has yellow (Y), magenta (M), and cyan ( C), which has four rows of nozzles 11 for ejecting black (B) ink and an ink tank 12 for storing ink of each color, and is mounted on a carriage (not shown) and is not shown together with the carriage. The recording medium 70 is main-scanned in the lateral direction (the direction of arrow B in FIG. 1 and the reverse direction) by the head moving means.

The recording medium 70 is provided with a plurality of pinch rollers 30 provided in the main scanning direction (the direction of arrow B in FIG. 1), which are brought into contact with the transport roller 20 by obtaining friction with the transport roller 20 and a pinch roller spring 31. The sheet is conveyed in a direction intersecting the main scanning direction (the direction of arrow A in FIG. 1) by the rotation of the conveying roller 20, and a sub-scan is performed to determine the recording position in the conveying direction. A discharge roller 40 for discharging the recording medium 70 after recording is provided on the downstream side in the transport direction, and the recording medium 70 is pressed against the discharge roller 40 at a position facing the discharge roller 40. A plurality of spurs 50 are arranged in the main scanning direction. The spur 50
The tip has a pointed shape so that unfixed ink on the recording medium 70 does not adhere. A platen 60 for maintaining the positional relationship between the recording medium 70 and the head 10 with high accuracy at a position where the head 10 performs recording is provided between the transport roller 20 and the paper discharge roller 40.

Next, the operation of the recording apparatus will be described.

First, the transport roller 20 is moved to the recording medium 70.
Is transported by a predetermined amount, and a sub-scan is performed to determine the recording position in this direction. Next, while the head 10 moves in the main scanning direction and performs main scanning for determining a recording position in this direction, ink is ejected and adheres to the recording medium 70 to perform recording. In this embodiment, the head 10 performs printing by discharging ink while performing main scanning in the direction of arrow B in FIG. 1, and after printing of a predetermined printing width is completed, the head 10 does not discharge ink as shown in FIG. It moves in the direction opposite to the arrow B direction and returns to the initial position. When there is a sub-scanning operation command, the transport roller 20 performs sub-scanning simultaneously with the return operation of the head 10. These operations are repeated a predetermined number of times to record one image.

Next, the structure of the platen 60 which is a feature of the present invention will be described with reference to the perspective view of the platen 60 shown in FIG.

As shown in FIG. 1, the contact surface of the platen 60 with the recording medium 70 (the upper surface in FIG.
The platen rib 61 for holding the recording medium at an appropriate recording position is provided, and the recording medium 70 is conveyed while being in contact with the platen rib 61, and is guided to the recording position. On both sides of the base portion 63 of the platen rib 61, the platen rib 6
A hole 62 is formed along the side surface of the first.

In the ink jet recording apparatus having the platen 60 having such a configuration, when ink adheres to the platen 60 such as when an image having a width larger than the width of the paper is erroneously printed, When a certain amount or more of ink is accumulated on the platen 60, the ink attached on the platen rib 61 is guided to the lower root portion 63 by gravity, and the ink attached between the plurality of platen ribs 61 tends to collect due to surface tension. At this time, the ink is attracted to the ink near the root portion 63 where the adhesion area is large and is difficult to move, and is guided to the root portion 63. In this manner, the ink gathers at the base 63 of the platen rib 61 and is smoothly discharged from the hole 62 along the side surface of the platen rib 61.

In the ink jet recording apparatus of this embodiment,
In this way, even if the ink adheres to the platen 60, the adhered ink can be discharged from the hole 62, so that the ink adheres to the platen 60 without the user cleaning the platen 60. Can be prevented.

(Embodiment 2) Next, an ink jet recording method according to Embodiment 2 will be described with reference to a plan view of a platen 60 portion of the ink jet recording apparatus shown in FIG. In the present embodiment, the configuration of the recording apparatus and the platen shape are the same as those in the first embodiment, and a description thereof will be omitted. Below,
A preliminary ejection method which is a feature of the ink jet recording method according to the present embodiment will be described.

Conventionally, preliminary ejection is performed after the head 10 is moved in the main scanning direction until the head 10 comes to a position outside the side edge of the sheet having the maximum width that can be used as the recording medium 70. However, in the present embodiment, when printing is performed on a sheet having a width smaller than the maximum sheet width, the head 10 is moved to a position outside the side edge of the sheet and opposed to the platen 60 to perform the preliminary ejection. I do.

That is, as shown in FIG. 3, when printing is performed on an A4 size sheet 71, the position outside the side edge of the sheet 71, that is, the sheet 7 on the platen rib 61a.
The head 10 is moved to a position opposing the position of the hole 62a on the side closer to the end of FIG. 1 (right side in FIG. 3) to perform preliminary discharge, and discharge ink is discharged from the hole 62a.
2, the head 10 is located at a position outside the side end of the sheet 72, that is, a position opposite to the position of the hole 62b on the side of the platen rib 61b near the end of the sheet 71 (right side in FIG. 3). To perform a preliminary discharge, and
The discharged ink is discharged from b. At this time, information on the size of the paper on which printing is performed may be input to the ink jet recording apparatus based on information from a personal computer or the like, and the preliminary ejection position may be determined according to this information.

As described above, in accordance with the size of the paper to be used, when the paper of each size is conveyed, the paper comes to a position near the outside of the paper end in the main scanning direction on the platen 60.
By providing the holes 62 and performing the preliminary ejection at the positions of the holes 62, the distance for moving the head 10 at the time of the preliminary ejection can be shortened as compared with the conventional example, and the recording is performed on one sheet of paper. Can be shortened.

[0023]

According to the present invention, by providing a hole along the side of the platen rib on the side of the platen rib, even if the ink is accidentally deposited on the platen, the adhered ink is naturally smoothed. Can be guided to the hole and discharged. This prevents the ink from sticking to the platen, and eliminates the need for the user to clean the platen.

Also, according to the size of the paper to be used, a hole is provided at a position near the outside of the paper end in the main scanning direction when the paper of each type is conveyed. By discharging the ejected ink from this hole, the moving distance of the head at the time of preliminary ejection can be shortened, and the printing time can be shortened.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an ink jet recording apparatus according to an embodiment of the present invention.

FIG. 2 is a detailed view of a platen of the ink jet recording apparatus of FIG.

FIG. 3 is a plan view of a platen portion of the ink jet recording apparatus of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Head 11 Nozzle part 12 Ink tank part 20 Conveying roller 30 Pinch roller 31 Pinch roller spring 40 Discharge roller 50 Spur 60 Platen 61, 61a, 61b Platen rib 62, 62a, 62b Hole 63 Root part 70 Recording medium 71 Paper (A4) ) 72 paper (B5)

Claims (3)

[Claims] 1. An ink jet recording apparatus comprising: a head for performing recording by discharging ink and attaching the ink to a recording medium; and a platen supporting the recording medium at a position facing the recording head at a recording position. 5. The ink jet recording method according to claim 1, wherein the platen has a platen rib serving as a protrusion for guiding the recording medium, and a hole formed along a side surface of the platen rib on a side of the platen rib. apparatus. And a head moving means for moving the head to a position on the platen opposite to a desired recording position of the recording medium. 2. The ink jet recording apparatus according to claim 1, wherein the holes are respectively provided at positions on the platen near the outside of the end of the recording medium of each size with respect to the moving direction of the head. 3. An ink-jet recording method using the ink-jet recording apparatus according to claim 2, wherein an edge of the recording medium to be recorded with respect to a moving direction of the head before ink ejection for recording. An ink jet recording method comprising: a step of moving the head to a position facing the hole provided in a position near the outside of the unit; and a preliminary ejection step of ejecting ink not contributing to recording thereafter.