JPS5968280A - Paper feeder for ink jet printer - Google Patents

Abstract

PURPOSE:To reduce the quantity of ink mist accumulated at the tip of a paper guide and prevent heavy contamination with an ink, by a method wherein a tip part of a paper guide for rectilinearly feeding a recording paper is formed in an acute angle shape, in an ink jet printer. CONSTITUTION:When the recording paper is clamped between rollers 17a, 17b, it is fed in the direction of an arrow A, is passed along the paper guide 16, and because of the strength of the paper 16 itself, the paper 16 is advanced between rollers 18a, 18b without being bent. Therefore, recording can be conducted from the leading end of the paper 6. Although ink mists are accumulated at the tip 16a of the paper guide 16 when an ink jetted from an ink-jetting head 10 travels toward a roller 15 by being deflected, since the tip 16a of the guide 16 is formed in a knife edge form and the upper surface thereof is mirror surface finished, the particle diameter of the ink mists accumulated at the tip 16a is so small that the ink particulates do not form visible smudges even when they are transferred onto the paper 6.

Description

[Detailed description of the invention] ■Technical field The present invention relates to a paper feeding device for an inkjet printer.
In particular, the present invention relates to a paper feeding device that has a small margin area on the recording paper that cannot be used for recording, which is necessary for conveying the recording paper.

■Prior art In general, in printers, etc., a platen and a recording head are opposed to each other, a recording paper is wound around the platen, and the leading edge of the recording paper is pulled using two rollers facing each other or one drive roller and a support plate. , ■ Recording is performed while feeding the paper line by line. Sometimes the platen is used as one drive roller.

Therefore, in a printer equipped with this type of paper feed device,
Paper cannot be fed unless at least the leading edge of the recording paper is pinched between rollers, and recording cannot be performed in the area from the nipping section to the recording section.

- An example is shown in Figure 1. To explain with reference to Figure 1,
A recording head 1 faces a platen roller 2, and a paper guide 3. A pressure roller 4 and a paper pail 5 are provided. Recording paper 6
is inserted between the platen roller 2 and the paper guide 3 from behind.

After being wound around the platen roller 2, the leading end is pressed and held by a paper pail 5. In this example, platen roller 2
is driven to rotate, and the "-N'QR paper 6 is fed by the clamping force of the paper pile 5 on the platen roller 2." It is not possible to record in the ranges Li (leading edge of the paper) and Li, 2 (the trailing edge of the paper), and in order to automatically feed the paper, it is necessary to add a large number of special paper guides.

In an inkjet printer, unlike other recording methods, no strong force is applied to the recorded portion of one sheet of paper. Therefore, the applicant set the path of the recording paper in a straight line and extended a plate-shaped paper guide to the vicinity of the recording position of the roller (platen roller). proposed a paper feeding device for an inkjet printer (Japanese Patent Application No. 77805/1983) in which the paper moves along a predetermined path. According to this, there is no need to support the leading edge of the paper, so it is possible to record on the leading edge of the paper, and since the paper guide is close to the recording position, it is possible to record on most of the area on the trailing edge of the paper.

However, when this method is adopted, the tip of the paper guide is close to the recording section, that is, the ink ejecting surface, so that invisibly small ink errors 1- accumulate at the tip of the paper guide. This ink mist transfers to the recording paper moving along the paper guide, causing stains and degrading recording quality.

■Purpose The present invention removes 44 visible large ink stains:
The first purpose is to improve the recording quality of inkjet recording, and the second purpose is to reduce the unrecordable area on the recording paper of the printer. A third purpose is to provide paper feed M[ for a printer.

(2) Structure In order to achieve the second object, in the present invention, the end of the paper guide near the recording position is formed at an acute angle. The particle size of the ink mist that accumulates at the edge of the paper guide corresponds to the thickness of the edge of the paper guide, so by making this part an acute angle, the particle size of the ink mist becomes smaller, effectively reducing the thickness of the paper guide. Dirt becomes so small that it cannot be seen by the human eye.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 2 shows a side view near the recording head of a -type printer. This will be explained with reference to FIG. The ink jet head IO is mounted on a carriage 11, and the carriage 11 is supported by a guide bar 12 arranged in a direction perpendicular to the drawing. Ink is ejected in the direction of arrow B (horizontal direction). i 3 a and 13
b is a deflection electrode, and 14 is a gutter that captures non-printing ink. The ink ejected from the 7r ink ejection head 10 is turned into particles and deflected in the vertical direction depending on the degree of charge.
It takes a flight trajectory as shown by the dotted chain line. Uncharged ink particles head toward the gutter 14, and other inter-particles head toward the roller 15.

The base of the paper card 16 is fixed to the printer body, and the vicinity of the other end (tip) lightly contacts the roller 15. The paper guide 16 has a tip 16a formed into a knife shape, and a raised portion 16b arranged perpendicular to the central axis of the ink flight trajectory. Below the paper guide 16 is a standing roller 17a, which is an extension of the ridged portion 16b.

+7b is arranged, and rollers 18a and 1.8b are arranged on the side of the paper guide 16. Roller 15.17
a and! , 8a have drive bells 1-19, respectively.
．． A motor (not shown) is connected via 20 and 21. The rollers 15 and 17a are driven at the same speed, and the roller 18a is driven at a slightly faster speed than these. When the recording paper 6 is sandwiched between the rollers 1.7a and +7b, it is fed in the direction of the arrow, and the paper guide 1
6, it advances between rollers 18a and 1.8b without being bent due to the strength of the recording paper itself, and is pulled out in the - direction.

In this embodiment, the horizontal distance between the vicinity of the paper guide tip 1.6a and the gutter 14 is set to about 1.5 mm.

FIG. 3 does not show an enlarged view of the vicinity of the paper guide tip 16a in FIG. 2. Referring to FIG. 3, in order to prevent contamination, the two sides S of the paper guide 1G are polished to a mirror finish, and the raised portion 16+) and S2 have a large number of longitudinal stripes 22. are formed at equal intervals.

In the above embodiment, the paper path consisting of the paper guide 16° rollers 17a, 17b, and 18a, 18b was made straight, but the paper guide I6 was bent to follow the roller 15, and the paper path in FIG.・The tip of the r-do-3 may be extended a little more. Further, in the second embodiment, nothing is provided between the roller J5 and the rollers 18a and 18b, but if the distance between them becomes large, it is better to provide a peg j4 in this area as well.

As described in ``Effects'', according to the present invention, the tip of the paper guide is made into a knife, so even if there is ink mist in this area, the ink mist will not become large, and the ink will move to the recording paper. C is also visible as 4. It maintains high recording crystal quality without becoming a big stain. Moreover, it is possible to perform recording on almost the entire surface of the recording paper.

[Brief explanation of drawings]

Figure 1 is a side view showing the paper feeding device of a conventional printer.
FIG. 2 is a side view showing a paper feeding device according to an embodiment of the present invention;
FIG. 3 is an enlarged perspective view of a part of the paper guide 16 shown in FIG. 2. FIG. 1: Recording head 2 nib tray 3: Paper guide 4: Pressure roller 5: Paper bail 6: Recording paper 10: Ink jet head 11: Carriage 12 Niga 7
r doper 13a, 13b: Deflection electrode 14 nigator +5, 17a
, 17b, 18a, 18b: rollers 19.20. '2
+-: Belt 22: Vertical strip 1 [Figure 3 21゛Sc 1 Continued from page 1 ■Inventor Kazumi Isima Inside Ricoh Co., Ltd., 1-3-6 Nakamagome, Ota-ku, Tokyo

Claims (3)

[Claims] (1) The ink jetting nozzle of the ink jetting head is opposed to the rotating roller, and the paper guide is provided with a tip protruding at least to the vicinity of the line connecting the ink jetting shaft of the ink jetting head and the roller, and the paper What is claimed is: 1. A paper feeding device for an inkjet printer, wherein the paper is fed by sandwiching the paper between a guide and the roller, wherein the tip of the paper guide is formed at an acute angle. (2) The paper guide is slightly inclined in a direction perpendicular to the flight axis of the jetted ink with respect to a plane orthogonal to the ink jetting axis. A paper feeding device for an inkjet printer according to claim (1). (3) The paper guide has vertical stripes formed on its surface facing the ink jet head, as claimed in claim (1) above.
Infusiera 1 to paper feeding device for a printer as described in item or item (2).