JP2002144650A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording apparatus capable of properly sucking sheets having many kinds of widths to feed them and capable of preventing the contamination of a suction fan or duct. SOLUTION: The ink jet recording apparatus has representative constitution consisting of a recording means for discharging ink to a sheet to record an image on the sheet, a platen opposed to the recording means to support the sheet, a plurality of suction ports provided to the platen, the suction duct provided under the platen, and a suction means for bringing the interior of the suction duct to a negative pressure state. The interior of the suction duct is divided into the first chamber on the side of the platen and the second chamber on the side of the suction means, and the first and second chambers are connected by the first opening part formed to the undersurface of the first chamber. A first ink absorbing member is provided in the first chamber, a second absorbing member is provided under the first opening part of the second chamber, and the second opening part connected to the suction means is provided to the second chamber between the first opening part and the second ink absorbing member.

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 which performs recording while sucking and conveying a sheet.

[0002]

2. Description of the Related Art Conventionally, silver halide photographic prints were superior to ink jet recording apparatuses for printing digital images.
It was a borderless photograph that could record the image quality and the entire photographic paper. However, recently, an ink jet recording apparatus which has been improved in image quality to be comparable to a silver halide photograph and has become capable of performing borderless recording has become equivalent to a silver halide photograph.

In an ink jet recording apparatus, it is desirable that ink be ejected perpendicularly from the ejection hole surface of the recording head. However, the ejection direction is inclined due to various factors, causing a shift in the ink landing position, resulting in poor image quality. May worsen. In this case, the smaller the distance (nozzle height) between the ejection hole surface and the sheet, the smaller the deviation of the landing position. However, when the nozzle height is reduced, the sheet may come into contact with the ejection hole surface due to curl (warpage) of the sheet or undulation due to ink absorption during solid image recording, and ink stains may adhere to the sheet.

Therefore, as shown in Japanese Patent Application Laid-Open No. 06-064175, there has been proposed a configuration in which a suction platen is provided at a position facing a recording head to reduce sheet height while suppressing curling and waving of a sheet. A suction platen is a box-shaped suction box that has a number of suction ports formed in the sheet contact surface and exhausts air from the inside using a fan to generate a negative pressure, which sucks and holds the sheet on the sheet contact surface. A platen that can be.

On the other hand, when performing marginless recording with an ink jet recording apparatus, a roll-shaped sheet is used, the sheet is automatically cut by a cutter in the sheet conveyance direction, and recording is performed in an area wider than the sheet width in the width direction. It is proposed in Kaihei 11-321016. In this case, the ink ejected outside the sheet width is absorbed by the absorber provided immediately below the sheet.

FIGS. 5 and 6 are cross-sectional views illustrating a platen of a conventional ink jet recording apparatus. FIG.
Shows a case where the recording apparatus has conveyed a sheet S1 having a minimum conveyable width w1, and FIG. 6 shows a case where a sheet S2 having a maximum conveyable width w2 has been conveyed. In the drawing, the right side of the platen is a reference for conveyance. A suction duct 103 having a suction fan 102 serving as suction means is provided on a platen 101.
Are mounted, and sheets S1 and S2 are
A large number of suction ports 101a provided in 1 are sucked by a suction fan 102 via a suction duct 103, and adhere to the surface of the platen 101.

[0007] Ink absorbers 104 to 106 are provided at both ends of the upper surface of the platen and at predetermined positions. These ink absorbers 104 to 106 absorb ink ejected outside the sheet width to perform borderless printing.
Reference numeral 4 denotes the left end of the sheet S2 having the maximum width w2, the ink absorber 105 is located outside the left end of the sheet S1 having the minimum width w2, and the ink absorber 106 is located outside the right ends of the sheets S1 and S2.

[0008]

However, in the above-mentioned conventional configuration, there is a problem when the conveyable sheet has a plurality of widths. For example, when the sheet S1 is shorter than the platen 101 as shown in FIG. 5, the ink mist generated during printing is sucked into the suction duct 103, so that the suction fan 102 becomes dirty with ink and malfunctions. In some cases, the suction force was reduced.

The sheet S conveyed as shown in FIG.
In the case where the ink absorber 105 is located on the lower surface of 2, the suction efficiency is reduced because the portion provided with the ink absorber 105 does not have the suction port 101a. In particular, it is still better if there are two types of sheet width that can be conveyed, but if there are more types, the ink absorber must be provided at each end position, so the area where the suction port 101a cannot be provided is large. In the worst case, the left half (non-reference side) of the platen 101 may be completely closed. Particularly when the sheet S2 having the maximum width w2 is conveyed by such a platen 101, the sheet S2
The left side of sheet 2 cannot be sucked at all, and the left end of sheet S2 may rise from platen 101 and come into contact with the ejection hole surface of the recording head, so that ink stains may adhere to sheet S2.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet recording apparatus capable of appropriately suctioning and conveying sheets of various widths and preventing contamination of a suction fan and a duct.

[0011]

In order to solve the above-mentioned problems, a typical configuration of an ink jet recording apparatus according to the present invention includes a recording unit for discharging ink onto a sheet to record an image, and a recording unit for recording an image on the sheet. An ink jet recording apparatus comprising: a platen opposed to support a sheet; a plurality of suction ports provided in the platen; a suction duct provided below the platen; and suction means for setting the inside of the suction duct to a negative pressure state. A first chamber in which the interior of the suction duct is divided into at least a first chamber on the platen side and a second chamber on the suction means side, and the first chamber and the second chamber are formed on a lower surface of the first chamber. Connected at an opening, a first ink absorber is provided in the first chamber, and a second ink absorber is provided below the first opening of the second chamber, and the second ink absorber is provided in the second chamber. One opening and second ink suction Between the body, characterized in that a second opening connected to the suction means.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the ink jet recording apparatus according to the present invention will be described. FIG. 1 is an overall configuration diagram of an ink jet recording apparatus according to the present embodiment, and FIG. 2 is a cross-sectional view illustrating a platen according to the present embodiment.

The ink jet recording apparatus shown in FIG. 1 is provided with a sheet 1 which is a roll-shaped medium. The sheet 1 is fed by a feed roller pair 2, and a tension is applied by a feed roller pair 2 and a conveying means 4. Recording means 3
To print an image by discharging ink. The sheet 1 on which the image is recorded is cut by the cutter 5 into a predetermined length, and is discharged and stacked by a discharge roller pair 7 on a discharge tray 8 arranged outside the apparatus. Chips of the sheet by the cutter 5 are dropped and stored in the waste box 6.

A platen 9 for supporting the sheet 1 is disposed at a position facing the recording means 3 so that the sheet 1 is kept flat even when ink is ejected from the recording means 3. The platen 9 has a plurality of suction ports 10 (FIG. 2).
The sheet 1 is conveyed while being suctioned to the platen 9 by sucking air through a suction duct 12 by a fan 11 which is suction means disposed below the platen 9, and a flat surface of the sheet 1. It is configured to ensure the property.

FIG. 2 shows a cross section XX in FIG. 1 and is a cross sectional view as seen from a direction perpendicular to the conveying direction of the sheet 1. In the figure, w1 indicates the minimum width of the sheet 1 that can be conveyed by the recording apparatus, and w2 indicates the maximum width. The recording apparatus according to the present embodiment conveys the sheet 1 on the one-side basis, and the right side in the drawing is the reference side. Therefore, the maximum width w2 extends to the left side of w1. The recording unit 3 reciprocates in a direction (main scanning direction) perpendicular to the transport direction to record an image on the sheet 1.

The suction duct 12 is divided into a first chamber 12a continuous with the suction port 10 of the platen 9 and a second chamber 12b on the fan 11 side, and both chambers are connected by a first opening 12c. The first opening 12c is disposed immediately below the conveyance path having the minimum sheet width w1.

In the first chamber 12a, first ink absorbers 15, 16 are provided on both sides of the first opening 12c. The first ink absorber 15 is arranged on the reference side (the right side in the figure) of sheet conveyance from the first opening 12c, and the first ink absorber 16 is arranged on the non-reference side (the left side in the figure). . In the figure, the widthwise dimensions of the first ink absorbers 15 and 16 are shown such that their ends coincide with the ends of the sheet 1.
It may be arranged further inside.

A second ink absorber 17 is provided in the second chamber 12b below the first opening 12c. In the drawing, the dimension in the width direction of the second ink absorber 17 is shorter than the width of the first opening 12c, but may be longer than this. A second opening 12d is provided between the first opening 12c of the second chamber 12b and the second ink absorber 17,
The fan 11 is connected to suck the air in the suction duct 12 so as to be in a negative pressure state.

Next, the operation will be described. During image recording, the fan 11 starts rotating before the sheet 1 enters the platen 9. When the sheet 1 enters the platen 9, the suction port 10 on the platen 9 is closed.
Due to the negative pressure in 12, the platen 9 is adsorbed on the surface. In this state, the recording unit 3 records an image while reciprocating in the main scanning direction, so that a high-quality image can be obtained without the sheet 1 floating from the platen 9.

In an ink jet type image recording apparatus, when ink is ejected from a recording head, fine mist-like ink mist is scattered in addition to the ink droplets that have been ejected. Therefore, ink mist is generated as the recording unit 3 starts recording, and floats in the air even after the ink is ejected.

When the fan 11 operates, the ink mist floating in the air is sucked from the suction port 10 of the platen 9 together with the surrounding air. The sucked ink mist passes through the suction port 10 outside the sheet 1 and falls into the first ink absorbers 15 and 16 provided thereunder to be absorbed. Furthermore,
The ink mist that has not been absorbed by the ink absorbers 15 and 16 can be absorbed by the second ink absorber 17 after passing through the first opening 12c.
Almost no ink mist exists in the air flowing through the fan 11 to the fan 11.

On the other hand, when performing borderless printing, the printing means 3 moves so as to discharge ink to a position slightly outside the sheet width. The ink discharged outside the sheet width is directly dropped on the first ink absorbers 15 and 16 and absorbed.

As described above, the inside of the suction duct 12 provided below the platen 9 is divided into the first chamber 12a and the second chamber 12b, and the ink absorbers 15 to 17 are provided in each of them. The suction port 10 can be arranged on the entire surface, and the sheet 1 can be reliably sucked to the platen 9.

In addition, since dropping ink and floating ink mist during borderless printing can be reliably absorbed,
Dirt on the fan 11 and the suction duct 12 can be prevented,
It is possible to prevent the occurrence of a failure of the suction means or a reduction in the suction force.

[Second Embodiment] Next, a second embodiment of the ink jet recording apparatus according to the present invention will be described. FIG. 3 is a cross-sectional view illustrating a platen according to the present embodiment. The same reference numerals are given to the same portions as those in the first embodiment, and the description is omitted.

In the above-described first embodiment, the recording apparatus that conveys the sheet 1 based on the one-sided reference with the right side as the reference has been described as an example. In the present embodiment, however, the central reference is used. Therefore, in the case of the maximum sheet width w2, it extends evenly on both sides with respect to the minimum sheet width w1.

In this embodiment, as in the first embodiment, the first opening 12c of the suction duct 12 has a minimum sheet width w.
It is arranged directly below one transport path and is connected to the second chamber 12b. The first ink absorbers 15 and 16 are disposed on the bottom of the first chamber 12a and on both sides of the first opening 12c. In FIG. 3, the widthwise dimensions of the first ink absorbers 15 and 16 are shown such that their ends coincide with the ends of the sheet 1, but they may be arranged to the inside of the sheet 1. A second ink absorber 17 is provided below the first opening 12c. A second opening 12d is provided between the first opening 12c of the second chamber 12b and the second ink absorber 17,
The fan 11 is provided ahead of this.

In this embodiment, the direction of the fan 11 is different from that of the first embodiment, and as shown in FIG.
By adjusting the direction of 11 to the direction of the second opening 12d, the air exhausted by the fan 11 can be discharged to the lower part of the first ink absorber 16, and the space efficiency in the vertical direction can be improved. .

[Third Embodiment] Next, a third embodiment of the ink jet recording apparatus according to the present invention will be described. FIG. 4 is a cross-sectional view illustrating a platen according to the present embodiment, and the same reference numerals are given to the same portions as those in the first embodiment, and the description will be omitted.

In the configuration of the first embodiment, the ink absorbed by the first ink absorber 16 may overflow from the first ink absorber 16 and flow toward the fan 11 if the amount is large. Therefore, in the present embodiment, a suction duct is provided below the first ink absorber 16 in the first chamber 12a of the suction duct 12.
It has a drain hole 18 which is a communication port communicating with the outside of 12. The drain hole 18 sends the ink absorbed by the first ink absorber 16 to the outside, so that the ink can be prevented from overflowing from the first ink absorber 16.

An absorber or a waste ink tank (not shown) is provided below the drain hole 18, and the ink absorbed by the first ink absorber 16 finally falls and is stored therein. The drain hole 18 is the first ink absorber
It may be provided not only below 16 but also below the first ink absorber 15 or the second ink absorber 17. The number is not limited to one, but may be plural.

[0032]

As described above, in the ink jet recording apparatus according to the present invention, the inside of the suction duct provided at the lower part of the platen is divided into at least two chambers, and the ink absorber is provided in each of the two chambers. The suction port can be arranged on the platen, and the sheet can be surely sucked to the platen.

In addition, since dropping ink and floating ink mist during borderless printing can be reliably absorbed,
It is possible to prevent the suction fan and the duct from being stained, and to prevent the occurrence of a phenomenon such as a failure of the suction unit or a decrease in the suction force.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of an inkjet recording apparatus according to a first embodiment.

FIG. 2 is a sectional view illustrating a platen according to the first embodiment.

FIG. 3 is a cross-sectional view illustrating a platen according to a second embodiment.

FIG. 4 is a cross-sectional view illustrating a platen according to a third embodiment.

FIG. 5 is a cross-sectional view illustrating a platen of an inkjet recording apparatus according to a conventional example.

FIG. 6 is a cross-sectional view illustrating a platen of an inkjet recording apparatus according to a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sheet 2 ... Supply roller pair 3 ... Recording means 4 ... Conveying means 5 ... Cutter 6 ... Dust box 7 ... Discharge roller pair 8 ... Discharge tray 9 ... Platen 10 ... Suction port 11 ... Fan 12 ... Suction duct 12a ... First One chamber 12b Second chamber 12c First opening 12d Second opening 15 First ink absorber 16 First ink absorber 17 Second ink absorber 18 Drain hole

Claims (3)

[Claims] A recording unit configured to record an image by ejecting ink on the sheet; a platen supporting the sheet facing the recording unit; a plurality of suction ports provided in the platen; A suction duct, and a suction means for setting the inside of the suction duct to a negative pressure state, wherein the inside of the suction duct is at least a first chamber on the platen side and a second chamber on the suction means side. Dividing, connecting the first chamber and the second chamber at a first opening formed on the lower surface of the first chamber, providing a first ink absorber in the first chamber, A second ink absorber is provided below the first opening, and a second opening connected to the suction means is provided between the first opening and the second ink absorber in the second chamber. Inkjet recording characterized by being provided Recording device. 2. The ink jet recording apparatus according to claim 1, wherein the first ink absorber is disposed below an area other than an area where a sheet having a minimum conveyable width is conveyed. 3. The ink jet recording apparatus according to claim 1, wherein the suction duct below the first and second ink absorbers has at least one communication port with the outside of the suction duct.