JPH07309044A - Image recording apparatus - Google Patents

Abstract

PURPOSE:To provide an image recording apparatus capable of eliminating the deterioration of image quality or contamination generated at the joint part at every scanning of an image. CONSTITUTION:An image recording apparatus has a feed device of a material to be recorded equipped with a paper feed roller 3b being a means fixing the material 2 to be recorded on a feed stand 4, a paper discharge roller 12 and a lower feed roller 9 being a feed means for intermittently feeding the feed stand 4 quantitatively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording apparatus for recording an image with a plurality of recording heads having a plurality of image recording elements, and more particularly to the conveyance of a recording material.

[0002]

2. Description of the Related Art Conventionally, as this type of image recording apparatus,
A so-called serial scan type recording apparatus is known, which converts a read image into a digital signal, processes the data converted into the digital signal, and then scans a recording head having a plurality of image recording elements multiple times to form an image. Has been.

In the apparatus as described above, that is, the recording apparatus in which the recording material is intermittently fed and recorded, the feeding accuracy of the recording material has a great influence on the image quality. for that reason,
Generally, a pulse motor with excellent positioning accuracy is used as a driving source for conveying the recording material, and members related to the feeding accuracy, for example, a conveyance roller that directly conveys the recording material and conveys the material have high accuracy. Is used.

[0004]

However, in reality, the amount of conveyance for each scan varies due to the recording material and the conveying roller slipping, and streak-like image deterioration occurs at the joint between the scans.

Further, as a recent trend, there is a demand for plural kinds of recording materials such as plain paper, coated paper, thick paper, and OHP sheet, but the physical properties (friction coefficient, thickness, etc.) of each recording material are different. There is a problem that the carry amount and the variation in the carry amount are different.

In addition, depending on the type of recording material, curling may occur in a low humidity environment or the like, which may hinder the conveyance. The curl of the recording material is caused by the property that the recording material expands and contracts depending on the amount of water in the recording material.Therefore, a difference in the amount of water between the front surface and the back surface due to changes in environmental humidity, etc. This is a phenomenon in which curl occurs due to the difference in shrinkage.

Further, there is another problem in the ink jet type recording apparatus for recording by making ink droplets adhere to the recording material. When recording is performed on a recording material having poor ink absorbability among various recording materials and the recording material is conveyed by a conveying roller, there is a problem that unabsorbed ink on the recording material is offset to the conveying roller.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and its object is an image capable of eliminating the deterioration of the image quality and the stain that occur in the joint portion of each scanning of the image. To provide a recording device.

[0009]

In order to achieve the above object, in the present invention, a recording material fixing means for fixing a recording material on a recording material conveying table, and the recording material conveying table are provided. It is characterized by having a recording material conveying device provided with a recording material conveying table conveying means for moving.

The recording material fixing means may include electrostatic attraction means.

It is preferable that the recording material carrying table carrying means intermittently feeds the recording material carrying table by a fixed amount.

[0012]

In the image recording apparatus configured as described above, the recording material fixing means for fixing the recording material on the recording material conveying table, and the recording material conveying table conveying for moving the recording material conveying table. The recording material transporting device including the means and the recording material transporting device is provided, and the recording material transporting base on which the recording material is fixed is moved to transport the recording material.

Since the recording material fixing means has the electrostatic adsorption means, the recording material is firmly fixed.

The recording material conveying table conveying means conveys the recording material stably by intermittently feeding the recording material conveying table in a fixed amount.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to illustrated embodiments.

(First Embodiment) FIG. 1 is a schematic vertical sectional view of an ink jet recording apparatus according to a first embodiment of the present invention, and FIG. 2 is a perspective view of FIG.

The transport mechanism of the recording material transport device 1 will be described with reference to FIGS. 1 and 2. Recording materials stacked in a paper feeding cassette (plain paper, coated paper, OHP sheets, etc.)
By rotating the paper feed roller 3a, only the uppermost one of the sheets 2 is separated and sent to the recording material transporting table 4.

The paper feed roller 3a stops at the position shown in the figure after one rotation, and the carrying force on the recording material 2 disappears, but the paper feed roller 3b rotates and the recording material 2 is placed on the recording material carrying table 4. Put.

The paper feed roller 3b is rotated and stopped until the tip of the recording material 2 contacts the paper discharge roller 12. Paper ejection roller 1
2 the front end of the recording material 2 and the paper feed roller 3b the recording material 2
The recording material 2 is fixed on the recording material conveying table 4 by pressing the rear end of the recording material 2. The paper feed roller 3b and the paper discharge roller 12 serve as a recording material fixing unit.

The recording material 2 is fixed to the recording material conveying table 4 and then is fed in the C direction while being fixed to the recording material conveying table 4, and the leading end of the recording material 2 comes under the recording head 18. By the way, stop.

The lower side of the recording material transporting table 4 has a rack shape, and the transporting lower roller 9 has a pinion shape. The transporting lower roller 9 as the recording material transporting table transporting means is driven by the pulse motor 8. The recording material transport table 4 is transported in the direction of arrow C. In FIG. 1, the recording material transport table 4 is at the right end when the recording material 2 is fed and at the left end when the recording is completed.

In FIG. 2, the lower conveyance roller 9 is driven by the pulse motor 8 via the belt 6 and the pulley 7.

Under this state, one line of recording is performed while scanning the carriage 19 having the recording head 18 along the rail 20 in the direction of arrow B by a scanning motor (not shown).

When the recording for one line is completed, the conveyance lower roller 9 is rotated in the direction of arrow A, the recording material 2 is fed by a predetermined amount, and the operation for recording the next line is repeated.

When the recording on the entire recording material 2 is completed, the recording material 2 is ejected by the ejection roller 12 to the ejection tray 2
It is discharged to 1.

Image recording is performed by the series of operations described above.

According to this structure, there are no more factors that cause variations in the amount of conveyance, as compared with the conventional method of directly feeding the recording material by the conveyance roller.

That is, there is no slippage between the recording material and the conveyance roller, variations in the conveyance amount caused by each scan, and differences in the conveyance amount due to differences in the materials of the various recording materials. As described above, in the serial scan type recording apparatus, the recording material is intermittently fed. That is, the recording material is repeatedly stopped by the conveying roller, conveyed, stopped, conveyed, and so on.
During stop → transport, the recording material and the transport roller slide according to the static friction coefficient value of the recording material at that time, during transport, slide according to the dynamic friction coefficient value, and during transport → stop, the dynamic friction coefficient Glide according to the value.

However, in the present transport method in which the recording material is brought into close contact with the rack-and-pinion type recording material transport base and the recording material transport base is transported, it is stable without depending on the friction coefficient between the recording material and the transport roller. The recording material is transported.

For the above reasons, this structure is effective as a method for reducing the seam stripes in the serial scan type recording apparatus.

Further, since the recording material 2 is conveyed in non-contact with the surface of the recording material 2, it is possible to prevent the ink not absorbed by the conveying rollers from being offset and deteriorating the image.

(Second Embodiment) In the second embodiment of the present invention,
An electrostatic attraction is used as a recording material fixing means on the recording material transport base 4, which will be described with reference to FIG.

The surface of the recording material carrying table 4 has a volume resistance of 10
The insulating layer has a thickness of ⁸ to 10 ¹⁰ Ω · cm or more, and the surface of the insulating layer is charged with a constant positive charge of several hundreds to tens of thousands of volts by a charging means 15, such as a charging roller, a charging brush, or corona discharge. The applied voltage depends on the structure, material,
The optimum value is set according to conditions such as the type of recording material. In this study, a charging blade was used as the charging means 15, and a voltage of 0.5 to 5 kV was applied.

When the recording material 2 is sent by the paper feed rollers 3a and 3b onto the charged recording material conveying table 4, the surface of the recording material 2 is removed by a conductive brush, a conductive roller, corona discharge, or the like. The surface of the recording material 2 is negatively charged by grounding or applying a negative charge of several hundred to tens of thousands of volts.

The recording material 2 can be strongly adsorbed on the recording material conveying base 4 by the electric charges of these two polarities. Therefore, even if the recording material 2 curls in the low humidity environment or the like, the recording material 2 is adsorbed on the recording material conveying base 4 by the electric charges of the both electrodes and curling can be prevented, which hinders conveyance. Disappears.

According to this configuration, an image without the above-mentioned connecting stripes can be obtained, and curling of the recording material which causes troubles when the recording material is conveyed can be prevented.

In the present invention, the recording material conveying table conveying means is a rack and pinion type, but it may be a so-called ball screw type, which can convey with high accuracy and can effectively form a joint line. In some cases it can be prevented.

Further, the effect of the present invention can be obtained if the image recording method is not only the ink jet type recording method but also the serial scan type recording method.

[0039]

The present invention has the above-described structure and operation, and has a recording material fixing means for fixing the recording material on the recording material conveying table, and a recording material for moving the recording material conveying table. Since the recording material conveying device including the conveying table conveying means is provided, the recording material conveying table on which the recording material is fixed is moved to convey the recording material. It is possible to eliminate the slippage between the sheet and the conveyance roller and the deterioration of the image that occurs in the joint portion for each scan, and to improve the image quality.

Since the recording material fixing means has the electrostatic attraction means, the recording material is firmly fixed and the conventional conveyance failure due to curling can be eliminated.

The recording material conveying table conveying means stably conveys the recording material by intermittently feeding the recording material conveying table, and the image quality can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of an inkjet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of FIG.

FIG. 3 is a schematic vertical sectional view of a second embodiment of the present invention.

[Explanation of symbols]

 1 Recording Material Conveying Device 2 Recording Material 3a Paper Feed Roller 3b Paper Feed Roller (Recording Material Fixing Means) 4 Recording Material Conveying Base 9 Lower Conveying Roller (Recording Material Conveying Base Conveying Means) 12 Paper Ejecting Roller Recording material fixing means) 14 Charge eliminating means (recording material fixing means) 15 Charging means (recording material fixing means) 18 Recording head

Claims (3)

[Claims] 1. A recording material conveying device comprising: a recording material fixing means for fixing a recording material on a recording material conveying table; and a recording material conveying table conveying means for moving the recording material conveying table. An image recording apparatus having a device. 2. The image recording apparatus according to claim 1, wherein the recording material fixing unit has an electrostatic attraction unit. 3. The image recording apparatus according to claim 1, wherein the recording material conveying table conveying means intermittently feeds the recording material conveying table by a fixed amount.