JPH0439054A - Ink jet printer - Google Patents

Abstract

PURPOSE:To blow off paper dust and the like to ensure the ejection of an ink drop by mounting a duct-integral fan which moves in the travel direction of a recording head as an integral part of the recording head and has an top end of an inverted-V shape in a direction that air flows along the printing surface of a recording medium. CONSTITUTION:On recording paper S fed into a printing part while being lightly depressed on a presser plate 45, characters, graphics, and the like in accordance with information to be recorded are written by an ink jet head 82 disposed on a carriage 80 running along two guide rails 81. At the time of writing, a duct-integral fan 83 on the carriage 80 blows air blown from an inverted-V shape air outlet against the both sides of the recording paper S and makes the air flow toward each end. In this manner, paper dust, foreign particle, and the like adhering on the recording paper S are blown off to be prevented from adhering on a nozzle. At this time, the air flow is so divided to the both sides as to avoid the nozzle surface of the ink jet head 82. Thus, a failure in ejecting ink caused by the air, such as askew flying, never occurs.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Use] The present invention relates to an inkjet printer that records dot images on a recording medium in accordance with input information by ejecting ink droplets.

[Prior Art] Inkjet printers that perform printing by selectively discharging ink from a large number of nozzles are superior to other types of printers in that they can perform recording and writing with low noise and high print quality.

However, if paper dust etc. from the recording paper adheres to the nozzle surface of the inkjet head, there is a problem in that ink droplet ejection failure occurs.To solve this problem, conventional inkjet printers have As shown in the cross-sectional view, the paper guide auxiliary plate 45 is pressed against the platen 46 on the downstream side of the inkjet head 82, and when the recording paper S passes between the platen 46 and the paper presser auxiliary plate 45, paper dust is generated. The structure was designed to wipe away the

[Problems to be Solved by the Invention] However, in the above-mentioned prior art, when folding paper with perforations or paper with large surface irregularities is used, paper dust attached to the perforations and recesses is removed by the paper guide auxiliary plate. It cannot be scraped off and adheres to the nozzle surface of the inkjet head,
There is a problem that ink droplet ejection failure is likely to occur.

In addition, if the contact surface of the paper guide auxiliary board with the recording paper is damaged by a paper jam, etc., the paper guide auxiliary board to scrape off the paper dust will roughen the printing surface of the recording paper and generate paper dust. There is also the problem that it can cause

[Means for Solving the Problems] The present invention is intended to solve these problems, and its purpose is to blow off paper dust and the like and ensure the reliable ejection of ink droplets regardless of the type of recording paper. Our goal is to provide an inkjet printer that makes it possible.

That is, the inkjet printer of the present invention has a duct-integrated fan that moves integrally with the recording head in the direction of movement of the recording head and has an inverted V-shaped tip in the direction in which air flows along the printing surface of the recording medium. By providing a
This is designed to keep paper dust away from the inkjet head to prevent ink droplet ejection failure due to paper dust.

[Example] Therefore, the illustrated embodiment will be described below.

FIG. 1 shows the entire structure of an inkjet printer which is an embodiment of the present invention, and its configuration will first be explained.

In the paper feed unit 10, a paper feed table 12 that is biased upward by a hopper spring 11 is disposed so as to be able to move up and down. A paper feed guide plate 14 leading from the paper feed roller 13 to a gate roller 21 (to be described later)
A separating claw 16 is provided on the top to separate the stacked recording sheets S one by one.

On the other hand, in the paper conveyance section 20 following this, a gate roller 21 connected to a driving force transmission mechanism (not shown) is disposed on the upper side of the paper conveyance section 20 so as to sandwich the travel path of a carriage 80, which will be described later. A driven roller 22 is disposed immediately after the gate roller 21 and is configured to rotate at the same circumferential speed via a paper feeding belt 23 suspended between the gate roller 21 and the paper feeding belt 21. 23
The idler 25 supported by one end of the idler lever 26 is in contact with the platen 46 directly below it, and is configured such that a constant tension is always applied by a tension spring 27 acting on the idler lever 26.

In the figure, reference numeral 29 indicates a fulcrum 3 above the gate roller 21 described above.
The paper presser roller lever 29 is pivotably supported on the paper presser roller lever 29 so as to be able to swing freely.A strong presser spring 33 is attached to the end of the upper arm 29a of the paper presser roller lever 29 to rotate the lever 29 counterclockwise in the figure. attached to the lower arm 29 of the lever 29
b The paper presser roller 32 supported at the lower end is connected to the paper feed belt 2.
3 is configured to be strongly pressed against.

On the other hand, 37 is a paper pail that approaches and separates from the paper feed belt 23 on the driven roller 22.
The structure is such that a plurality of them are fixed at intervals of 6. The paper pail lever 38, which supports the paper pail 37 at one end, has its base end fixed to a support shaft 39 supported on the lower side of the driven roller 22, as shown in FIG. Pinion 4 meshing with sector 40
1, the paper pail 37 is moved to the paper feed belt 23 immediately before the trailing edge of the recording paper S passes over the gate roller 21.
It is configured so that the recording paper S is fed out by being pressed against the top.

In the discharge section 60, a pair of intermediate paper discharge roller shafts 62 and 65 are arranged on the downstream side adjacent to the driven roller 22. A plurality of short intermediate paper ejection rollers 63 made of an elastic material are fixed at intervals to one of the intermediate paper ejection roller shafts 62 disposed below the paper ejection guide plate 61, and each of these rollers 63 has a As shown in FIG. 3, thin-walled cylindrical portions 64, 64 with a slightly smaller diameter are integrally formed at both ends thereof, and a thin plate-shaped jagged roller 66.64 is fixed to the other intermediate paper ejection roller shaft 65. 66 to these thin-walled cylindrical portions 64.
By contacting and rolling against the recording paper S 64, the recording paper S can be ejected without applying excessive force.

On the other hand, reference numerals 68 and 71 denote a pair of paper ejection roller shafts disposed on the downstream side of the hot air drying unit 90, which will be described later.
As shown in FIG. A thin plate-shaped jagged roller 72 is fixed so as to be slightly shifted in the axial direction with respect to the wrapper part 70 and slightly matched in the radial direction, and is directed toward the conveyance direction of the dry-treated recording paper S. The sheet is configured to form a large wave, and the resulting stiffness causes the sheet to protrude flatly and to be sent to the sheet discharge tray 14.

In the figure, reference numeral 80 denotes a carriage that runs along two guide rails 81 and 81 suspended above the printing unit so as to be orthogonal to the recording paper conveyance direction. In addition to an inkjet head 82 that ejects ink onto the recording paper S from one nozzle, a duct-integrated fan 83 that blows away paper powder, dust, etc. adhering to the recording paper S is provided.

That is, as shown in FIG. 5.6, a duct-integrated fan 83 having an inverted V-shaped outlet is provided on the downstream side of the carriage 80 in the paper conveyance direction. For example, the air is diverted to the left and right along the vertical baffle plate 84 provided below, avoiding the nozzle surface of the head 82, and the air is guided to the other side along the surface of the recording paper S. It is configured to blow away paper powder etc. that have adhered to the surface.

Reference numeral 90 in the figure is a hot air drying unit that blows hot air onto the recording paper S that has undergone the recording/writing process to dry it.

Next, the basic printing operation of the above-mentioned apparatus will be explained.

When the paper feed roller 13 starts rotating in response to a paper feed signal and feeds out the recording paper S on the paper feed tray 12, only one of the uppermost recording papers S is separated by the separation claw 16, and then the paper feed guide plate 14
The paper is guided by the carry-in guide plate 43 and reaches the gate roller 21, where it passes between the paper feed belt 23 and the paper press roller 32 that is in strong pressure contact with it, and is sent to the printing section.

The recording paper S, which is fed into the printing section while being lightly pressed by the presser plate 45, is moved along the two guide rails 81 and 81.
Character 1 corresponding to the information to be recorded by the inkjet head 80 disposed on the carriage 80 traveling along the
Figures etc. are written. During this writing, carriage 8
The duct-integrated fan 83 on the top 0 blows the air blown out from the inverted V-shaped outlet to both sides of the recording paper S and directs it to the other side to remove paper powder and dirt attached to the recording paper S. etc. to prevent paper powder, etc. from adhering to the nozzle. At this time, the blown air is divided to the left and right to avoid the nozzle surface of the inkjet head 82, so there is no occurrence of ink ejection defects 1 such as bending due to air, and the recording paper is Since the paper dust on the recording paper is blown away, regardless of the order of the type of recording paper, such as perforated folded paper, the paper dust on the recording paper is reliably blown away, and it is possible to prevent ink droplet ejection failure due to paper dust.

On the other hand, at the beginning of paper feeding, the paper pail lever 38
is rotated upward by the pinion 41 that meshes with the sector 40, and separates the paper pail 37 supported at the tip from the paper feed belt 23, so that the recording paper S that has undergone the record writing process is pulled up. The dot image is not disturbed by passing under the paper pail 37 (paper discharge section 6).
sent to o.

By the way, as described above, the intermediate paper ejection roller disposed immediately after the driven roller 22 has thin cylindrical portions 64 and 64 at both ends.
an intermediate roller 63 provided with these thin-walled cylindrical portions 64 .
64, the recording paper S that has been subjected to the ink writing process is loosely sandwiched between them, and furthermore, the thin jagged rollers 66 write on the surface of the recording paper S. The printed image is guided by the paper discharge guide plate 61 without being disturbed and fed into the hot air drying unit 90, where it undergoes the required drying process with hot air and is transferred to the paper discharge tray by the paper discharge rollers 69 and 72. 74
is discharged to.

This operation continues, and just before the trailing edge of the recording paper S passes over the gate roller 21, a paper edge detection sensor (not shown) disposed here detects this state, and the pinion 41, the paper pail lever 38 is lowered via the sector 40, the paper pail 37 at the tip thereof is brought into contact with the paper feed belt 23, and the recording paper S, which has been cut off from being conveyed by the gate roller 21, is moved to the driven roller 22.
and the thin jagged rollers of the paper pail 37, the hot air drying unit 90 can be used without adversely affecting the recorded and written image.
send it towards.

〔Effect of the invention〕

As described above, according to the present invention, the duct moves integrally with the recording head in the moving direction of the recording head, and has an inverted V-shaped tip in the direction in which air follows the printing surface of the recording medium. Equipped with a body-shaped fan, regardless of the type of recording medium, such as folded paper with perforations or paper with large irregularities, paper dust adhering to the recording medium is reliably blown away just before printing, and the paper dust is transferred to the inkjet head. This can be expected to have the effect of preventing ink droplets from being ejected incorrectly due to paper dust.

[Brief explanation of the drawing]

Fig. 1 is an overall view of an apparatus constituting an embodiment of the present invention, Fig. 2 is a view showing the paper pail mechanism, and Figs. 3 and 4 are sectional views showing the rollers on the paper ejection side. , Figure 5, Figure 6
The figure shows a state in which paper dust and the like are removed by the duct-integrated fan. FIG. 7 is a sectional view of a conventional inkjet printer. 13... Paper feed roller 21... Gate roller 32 ・ 37 ・ 38 ・ ・ 63 ・ ・ 64 ・ ・ 66 ・ 69 ・ ・ 70 ・ ・ 72 ・ ・ 80 ・ ・ 82 ・ ・ 83 ・ 84 ・ ・

Claims (1)

[Scope of Claims] 1) In a printing device that records a dot image on a recording medium according to input information by ejecting ink droplets, the recording head is integrated with the recording head in the vicinity of the recording head in the direction of movement of the recording head. What is claimed is: 1. An inkjet printer, characterized in that the inkjet printer moves in the direction of the printing surface of the recording medium and is provided with a duct-integrated fan in a direction in which air flows along the printing surface of the recording medium. 2) The inkjet printer according to claim 1, wherein the duct end of the duct-integrated fan has an inverted V-shape.