JPH1191981A - Paper feed roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a trouble wherein a trace mark is heretofore formed on a recording paper and a slide occurs to the paper, in a paper feeding mechanism, such as a printer device, to record various information, such as image information, on a recording paper. SOLUTION: Resultant from the continuously decrease of the outside diameter of the end part on one side of the protrusion forming part of a paper feeding roller 1, a pressure exerted on a recording paper 6 is continuously changed in the vicinity of the end part of a protrusion forming part. This constitution prevented from formation of a trace mark at the recording paper 6 due to a local change in a pressure. Further, by forming a driven roller 3 integrally with a metallic shaft, the biting force of the recording paper 6 of a fine protrusion 7 is increased, and a slip hardly occurs between the paper feeding roller 1 and the recording paper 6 against a running load generated during reciprocation of the recording paper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed roller used in a printer or the like for recording various information such as video information on recording paper.

[0002]

2. Description of the Related Art In recent years, printer apparatuses which record various video signals on recording paper in full color have begun to spread. Under such circumstances, there is a demand for quality improvement such as paper feeding accuracy of a paper feeding roller used in a printer device and cost reduction.

Hereinafter, a conventional paper feed roller will be described with reference to FIGS. 5, 6 and 7. FIG.

FIG. 5 is a schematic perspective view of a conventional paper feed roller and a driven roller. FIG. 6 is a partial cross-sectional view of a conventional paper feed roller and a driven roller. In the figure, reference numeral 1 denotes a paper feed roller which is rotationally driven by a driving means (not shown), and has two protrusion forming portions 2 formed at predetermined intervals. Reference numeral 3 denotes a driven roller which rotates together with the paper feed roller 1, and is formed by printing rubber portions 5 at two places on both ends of a metal shaft 4. Reference numeral 6 denotes a recording sheet nipped and conveyed by the paper feed roller 1 and the driven roller 3. Reference numeral 7 denotes a large number of minute projections formed on the surface of the projection forming section 2.

The operation of the conventional paper feed roller configured as described above will be described below.

In FIG. 5, a recording paper 6 nipped by a paper feed roller 1 and a driven roller 3 with a predetermined force is conveyed as the paper feed roller 1 rotates. here,
As a configuration at the time of conveyance, as shown in FIG. 6, minute projections 7 formed on the surface of the projection forming portion 2 of the paper feed roller 1 are formed.
However, there is a case where the recording paper 6 has been cut.

FIG. 7 is a partial sectional view of another conventional paper feed roller and driven roller. In FIG. 7, the driven roller 3 is entirely a metal shaft.

[0008]

However, in the above-mentioned conventional paper feed roller, the rubber portion 5 has to be burned on the driven roller 3, so that the cost of the driven roller 3 is increased. Further, the recording paper 6
However, there is also a problem that a local pressure change occurs and a trace is easily generated on the surface of the recording paper 6, and in particular, a gloss-treated one on the surface of the recording paper 6 has a problem. . Further, if the rubber hardness of the rubber portion 5 is softened in order to reduce the trace, the biting force of the minute projections 7 into the recording paper 6 is reduced, and the slip is easily generated between the paper feed roller 1 and the recording paper 6. However, the recording paper 6 cannot be smoothly conveyed.

Further, in the paper feed roller 1 shown in FIG. 7, since the driven roller 3 is entirely made of a metal shaft, a large force is locally applied to the recording paper 6 at the end of the projection forming portion 2. As described above, there is a problem that traces are easily generated on the back surface.

An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a paper feed roller which does not cause a trace on a recording sheet and can smoothly convey the recording sheet.

[0011]

In order to achieve the above object, a paper feed roller according to the present invention has at least one projection formation area having a large number of fine projections on the surface of the paper feed roller. In the vicinity of one end, the outer diameter of the projection forming area is continuously reduced in the outward direction of the projection forming area, so that no trace is formed on the recording paper and the paper feed roller which does not slip with the recording paper. The purpose is to provide it at low cost.

[0012]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 of the present invention comprises at least one projection forming area having a large number of fine projections on the surface of a paper feed roller, and at least one end of the projection forming area. In the vicinity, the paper feed roller is configured such that the outer diameter of the projection forming area continuously decreases as going outward of the projection forming area.

According to this configuration, the outer diameter of the projection forming area is continuously reduced toward the outside of the projection forming area, so that the paper feed roller applies the recording paper near the end of the projection forming area. The pressure decreases continuously,
No visible traces occur. In addition, since the trailing roller is less likely to be formed, the driven roller can be made of a hard material such as a metal shaft, and the pressure applied to the minute projections is increased, so that slippage is less likely to occur between the paper feed roller and the recording paper.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. (Embodiment 1) FIGS. 1A and 1B are front sectional views of an image printer using a paper feed roller according to the present embodiment. In FIG. 1, reference numeral 8 denotes an ink sheet coated with three primary color inks, 9 denotes a supply reel around which the ink sheet 8 before use is wound, 10 denotes a take-up reel around which the ink sheet 8 is wound, and 11 denotes a supply reel 9 And an ink cassette holding the take-up reel 10, a thermal head 12 for printing on the recording paper 6, a platen roller 13 for holding the ink sheet 8 and the recording paper 6 together with the thermal head 12, and a recording paper 6
Is a driven roller for pressing the recording paper 5 against the paper feed roller 1, and 14 and 15 are a light emitting element and a light receiving element for detecting the position of each color of the ink sheet 1. FIG. 2 is a schematic perspective view of the paper feed roller and the driven roller of the present embodiment. In FIG. 2, 1 is a paper feed roller, 2 is a projection forming portion provided at two places at both ends of the paper feed roller 1, and 3 is a driven roller so as to become thin in the opposite direction, and is formed integrally with a metal shaft. I have. FIG. 3 is a partial cross-sectional view of the paper feed roller and the driven roller according to the present embodiment. In FIG.
Is a minute projection provided on the surface of the projection forming portion 2, and can convey the recording paper 6 by cutting into the recording paper 6.

The operation of the image printer using the paper feed roller of the present embodiment configured as described above and the relationship between the paper feed roller and the recording paper will be described.

First, when the thermal head 12 is retracted as shown in FIG. 1A, recording paper is supplied from a recording paper supply mechanism (not shown) to the position of the paper feed roller 1 and the driven roller 3, and The recording paper is nipped between the paper feed roller 1 and the driven roller 3 with a predetermined force. Then, when the paper feed roller 1 is rotated in a predetermined direction, the recording paper 6 is conveyed in the direction of arrow A to a predetermined position.

Next, the ink sheet 8 is conveyed in the direction of arrow C to a predetermined position (the head position of yellow ink).
At this time, the transport position of the ink sheet 8 is detected by the light emitting element 14 and the light receiving element 15.

Then, as shown in FIG. 1B, the thermal head 12 is pressed against the platen roller 13, and while the ink sheet 8 is conveyed in the direction of arrow C, the paper feed roller 1 is rotated in a predetermined direction so that the recording paper 6 is rotated. To the predetermined position (image length) in the direction of arrow B. At this time, a predetermined voltage is applied to the thermal head 12, and a predetermined image (yellow color) is printed on the recording paper 6.

Next, as shown in FIG. 1A, the thermal head 12 is retracted, the recording paper 6 is transported in the direction of arrow A to a predetermined position, and the ink sheet 8 is moved in the direction of arrow C at a predetermined position (magenta (Head position of ink).

Next, as shown in FIG. 1 (b), the thermal head 12 is pressed against the platen roller 13, and the paper feed roller 1 is rotated in a predetermined direction while the ink sheet 8 is being conveyed in the direction of arrow C. 6 in the direction of arrow B to a predetermined position (image length). At this time, a predetermined voltage is applied to the thermal head 12, and a predetermined image (magenta) is printed on the recording paper 6.

Next, the thermal head 12 is retracted as shown in FIG. Then, the recording paper 6 is transported in the direction of arrow A to a predetermined position, and the ink sheet 8 is transported in the direction of arrow C to a predetermined position (the top position of cyan ink).

Next, the thermal head 12 is pressed against the platen roller 13 as shown in FIG. And then
While transporting the ink sheet 8 in the direction of arrow C, the paper feed roller 1 is rotated in a predetermined direction to transport the recording paper 6 in the direction of arrow B to a predetermined position (image length). At this time, a predetermined voltage is applied to the thermal head 12, and a predetermined image (cyan) is printed on the recording paper 6.

With the above operation, a full-color image is printed on the recording paper 6. Finally, as shown in FIG. 1A, the thermal head 12 is retracted, the paper feed roller 1 and the driven roller 3 release the nipping of the recording paper 6, and the recording paper discharge mechanism (not shown) is used. Is discharged out of the apparatus.

The recording paper 6 reciprocates while being held between the paper feed roller 1 and the driven roller 3. At this time,
As shown in FIG. 3, since the outer diameter of one end of the protrusion forming portion 2 of the paper feed roller 1 is continuously reduced, the pressure applied to the recording paper 6 is near the end of the protrusion forming portion 2. It is changing continuously. As a result, no trace is produced on the recording paper 6 due to a local change in pressure. In addition, since the driven roller 3 shown in FIG. 2 is integrated with the metal shaft, the biting force of the minute projections 7 on the recording paper 6 is increased, and the paper feed is performed against the running load generated during the reciprocating movement of the recording paper. Slip does not easily occur between the roller 1 and the recording paper 6.

As described above, according to the present embodiment, since the outer diameter of one end of the projection forming portion 2 of the paper feed roller 1 is continuously reduced, the recording paper 6 has a local area. No traces are produced due to the change in pressure. In addition, since the driven roller 3 shown in FIG. 2 is integrated with the metal shaft, the biting force of the minute projections 7 on the recording paper 6 is increased, and the paper feed is performed against the running load generated during the reciprocation of the recording paper. Slip does not easily occur between the roller 1 and the recording paper 6.

In this embodiment, two projection forming portions 2 are provided on the paper feed roller 1. However, the number of the projection forming portions 2 is not limited, for example, three projection forming portions are provided as shown in FIG.

[0027]

As described above, according to the present invention, the pressure applied to the recording paper can be continuously changed in the vicinity of the end of the projection forming area, and the recording paper has a trace shape caused by a local pressure change. Paper feed roller that does not cause the problem. In addition, a rigid roller can be adopted as the driven roller of the partner, and there is no slippage between the paper feed roller and the recording paper, and an excellent effect that the cost of the paper feed roller capable of smoothly conveying the recording paper can be reduced. It is.

[Brief description of the drawings]

FIG. 1A is a front cross-sectional view of an image printer in a retracted state of a thermal head according to a first embodiment of the present invention. FIG. 1B is a front cross-sectional view of the image printer in a pressed state of the thermal head in the first embodiment of the present invention.

FIG. 2 is a schematic perspective view of a paper feed roller in the embodiment.

FIG. 3 is a sectional view of a main part of the paper feed roller according to the embodiment.

FIG. 4 is a sectional view of a main part of the paper feed roller according to the embodiment;

FIG. 5 is a schematic perspective view of a conventional paper feed roller.

FIG. 6 is a sectional view of a main part of a conventional paper feed roller.

FIG. 7 is a sectional view of a main part of a conventional paper feed roller.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 paper feed roller 2 protrusion assembly 3 driven roller 6 recording paper 7 minute protrusion

Continued on the front page (72) Inventor Takayuki Koike 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (2)

[Claims] 1. A paper feed roller for transporting recording paper, comprising at least one protrusion forming area having a large number of fine protrusions on the surface of the paper feed roller, and near one end of the protrusion forming area. A paper feed roller, wherein the outer diameter of the projection forming region is continuously reduced in the longitudinal direction. 2. A paper feed roller for transporting recording paper, comprising two projection forming areas having a large number of minute projections on the surface of the paper feeding roller, the side facing the longitudinal direction of the projection forming area. Wherein the outer diameter of the paper feed roller is continuously reduced.