JP3019877B2 - Printing mechanism of inkjet printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing mechanism for a printer.

[0002]

2. Description of the Related Art As shown in FIG.
The recording paper 1 was in contact with the platen 21 whose gap with the print head 9 was controlled, and a dot image was formed on the recording paper 1 on the surface thereof. In addition, in an ink jet printer that discharges ink droplets to form a dot image on recording paper, printing may be performed accidentally when there is no paper or ink droplets may spill out of the print head 9. Has a platen 2
1 has a problem that the newly inserted paper is stained by the ink remaining without drying.

In the case of using a hot-melt type ink which melts and liquefies an ink which is solid at normal temperature and discharges the ink, the ink remaining on the platen solidifies and is usually removed by wiping. There is also a problem that it is impossible, and the newly inserted paper is hindered by the ink and cannot be fed.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in view of such a problem.
It is an object of the present invention to provide a printing mechanism capable of reliably outputting even if ink is accidentally ejected to a place where there is no paper without any influence.

[0005]

Means for Solving the Problems That is, the present invention relates to
In order to achieve the above object, a printing mechanism of an ink jet printer provided with a recording / writing means for ejecting ink droplets and forming a dot image on a recording medium in accordance with input information.
The paper transport surface on the upstream side of the recording / writing means in the paper transport direction.
Paper guide at the same height as
The lower part of the unit at the same height as the paper transport surface
A pair of paper feed rollers is provided, and the paper guide and paper feed roller
The recording medium is suspended and transported during
It is designed to perform recording and writing on a recording medium.
Paper transport method of the support member supporting the paper feed roller.
Make sure that the surface on the hand side is close to the nip between the paper feed rollers.
It is designed to be gently inclined .

[0006]

[Embodiments] The following embodiments will be described.

FIG. 1 shows the entire printing mechanism of a printer according to an embodiment of the present invention, and FIG. 2 is an enlarged view showing the details of the essential parts.

Reference numeral 8 in the figure denotes a head carrier that runs along two guide shafts 6 and 7 suspended on left and right frames (not shown). The recording paper 1 moves left and right in the width direction of the recording paper 1 with the rotation of the recording paper 1. A print head 9 is provided on the head carrier 8 so as to form a dot image on the recording paper 1.

On the other hand, the bottom frame 2 of the printer body
2 includes a paper transport surface L on the upper side of the print head 9 in the paper transport direction.
The paper guide 2 having the same height as that of the paper guide is bent one step higher,
Also, the paper transport direction is located on the lower side of the print head 9 in the paper transport direction.
The slope on the hand side should be gently sloped toward the upper side in the paper transport direction.
Near the nip between the paper feed roller 14 and the paper press roller 15
There is a bearing 18 extended to the side,
The recording paper 1 in cooperation with the paper holding roller 15
L, a paper feed roller 14 that conveys the paper along the axis L is supported by a shaft.
Paper feed motor 12 via a main gear 13 fixed to the end
It is configured to be driven and rotated.

Reference numeral 3 in FIG.
The paper guide auxiliary plate for holding the paper 1 is shown.
9 is a paper pusher for pressing the recording paper 1 against the paper feed roller 14.
Pressing force is applied to the paper press roller 15 via the feed lever 16
4 shows a paper holding spring to be used.

In the device configured as described above,
Also, the recording paper 1 is fed in such a manner that the recording paper 1 is brought into sliding contact with the paper guide 2.
In other words, the leading end of the recording paper 1 has a loose surface on the upper side in the paper transport direction.
The paper feed roller 14 is guided by the inclined bearing 18.
To the nip of the paper press roller 15, and
Loaded under tension by the transport action of the rollers 14 and 15
Is done. Then, the recording paper 1 is conveyed through this
First, ink droplets are ejected onto the surface of the recording paper 1 to perform recording and writing.
When this is done, the recording paper 1 comes into contact with other objects between them.
Therefore, it cannot be transported smoothly without chattering.
In addition, it receives a good recording and writing process.

On the other hand, between the paper feed roller 14 and the paper guide 2
If the recording paper 1 is not sent to the
When ink droplets are ejected from the character head 9,
The ejected ink droplet is located below the paper transport surface L.
Falling onto the bottom frame 22 and recording paper
Ink drops adhere to recording paper 1 even when 1 is sent
Can be prevented beforehand.
It is.

In order to provide a space on the back side of the printing surface 20, as another embodiment of the structure of the present embodiment of the paper guide 2, the paper guide 2 does not have to be bent.

Further, in a hot-melt type ink jet printer, the structure around the print head becomes high in temperature due to the nature of the ink, and the recording paper is warmed accordingly, and the ink is originally discharged onto the recording paper. While the ink that cools and solidifies when it is in the liquid state becomes longer, it penetrates into the recording paper and becomes an unclear dot image, whereas the back side of the recording paper printing surface is a space, The recording paper is cooled by the space, and a clear dot image can be formed on the recording paper.

[0015]

As described above, according to the present invention, the recording
A medium provided on the upper side of the recording / writing means in the paper transport direction.
Hanging between the guide and a pair of paper feed rollers provided on the lower side
Transported, so that it may come into contact with other objects during the transport process.
There is no occurrence of chatter on the recording medium due to
In addition to always enabling good recording and writing,
Even if the recording medium swells due to recording and writing
By releasing this part to the back side of the recording medium,
It is possible to avoid contact with the recording and writing means,
Furthermore, under the condition that the recording medium is not sent,
Even if ink drops are ejected,
The recording medium is contaminated by the ink droplets
Can be prevented beforehand. In addition, a paper feed row
Gently tilt the surface of the support member that supports the
And extended to near the nip between the paper feed rollers
Gap to prevent ink droplets from adhering to the recording / writing area.
Support the leading edge of the recording medium
Hold the recording medium in both rows along the slope of the holding member.
It can be automatically loaded into the nip part of the la.

[Brief description of the drawings]

FIG. 1 is an overall view showing one embodiment of the present invention.

FIG. 2 is an enlarged view showing a main part of the above device.

FIG. 3 is a detailed view showing a conventional technique.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 recording paper 2 paper guide 3 paper guide auxiliary plate 4 belt driven pulley 5 timing belt 6 head carrier guide shaft B 7 head carrier guide shaft A 8 head carrier 9 print head 10 timing belt fixing plate 11 drive motor 12 paper feed motor 13 main Gear 14 Paper feed roller 15 Paper press roller 16 Paper press lever 17 Paper press lever fulcrum shaft 18 Paper feed roller bearing 19 Paper press spring 20 Recording paper print surface 21 Platen

Claims (2)

(57) [Claims] A recording / writing unit configured to form a dot image corresponding to input information on a recording medium by discharging ink droplets .
In the printing mechanism of the ink jet printer, the recording / writing means is positioned on the upper side in the paper transport direction with the same paper transport surface.
While providing a paper guide having a height, the recording and writing means
On the lower side of the paper transport direction, a pair of
The paper guide roller and the paper feed roller
The recording medium while suspending and transporting the recording medium between the
Means for recording and writing on the recording medium
A printing mechanism for an ink jet printer. 2. A support member for supporting the paper feed roller.
Hold the surface on the upper side in the paper transport direction between the paper feed rollers.
Characterized in that it is gently inclined toward the vicinity of the
Item 2. A printing mechanism of the inkjet printer according to Item 1.