JP2579733Y2 - Paper guide mechanism in 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 paper guide mechanism in a printer. In particular, the present invention relates to a paper guide mechanism for detecting a paper or reading an ID when the paper passes through a sensor in front of a sensor. This is suitable for use in a paper guide mechanism for preventing the distance to the sensor from fluctuating due to hitting.

[0002]

2. Description of the Related Art Conventionally, a horizontal printer which feeds paper horizontally without winding it around a platen has been used. 3 to 5 are diagrams for explaining an example of a conventionally used horizontal printer. FIG. 3 is a side view showing a main part of the printer, FIG. 4 is a plan view including a broken part, and FIG. 5 is a perspective view. As shown in FIG. 3, in a horizontal printer, a carriage 3 is provided above a platen 1, and a print head 2 is mounted on the carriage 3 with its print surface facing downward. A protector 12 is arranged in a state of being fixed to the carriage 3, and the paper 10 is fed between the protector 12 and the platen 1 by the feeding action of the tractor 9. The protector 12 functions as a guide when the paper 10 is fed.

The carriage 3 is supported by a main shaft 4 and a guide shaft 5 supported by a side frame so as to be movable in a direction perpendicular to the direction in which the paper 10 is fed. Predetermined character information and the like are printed on the paper 10 while moving in parallel with the platen 1 in synchronization. The feature of the horizontal printer is that the paper 10 can be fed horizontally without winding the paper 10 around the platen 1 as described above. Generally, as shown in FIG. It has both routes 10a.

[0006] As shown in a detailed view of a sheet sensor section in FIG. 6, a sensor 28 (hereinafter referred to as a sheet sensor) is provided adjacent to the feed roller 6b in a state of being attached to the front sheet guide lower 27b. When the cut sheet is fed, the sheet sensor 28 detects the sheet and reads the ID. That is, when the cut sheet is fed, the sheet 10 passes through the cut sheet route 11 while being guided by the front sheet guides 15a and 15b, and
Pass in front of 8. At this time, the paper holding spring 29
Then, the sheet 10 is moved to the front sheet guide lower 27b.
Side of the paper 10 and the paper sensor 2 so as to prevent the paper 10 from fluttering and floating.
8 is kept constant.

[0005]

Conventionally, the effect of reading the ID of the paper sensor 28 has been enhanced by keeping the distance between the paper 10 and the paper sensor 28 constant in this manner. There was such an inconvenience. That is, in the apparatus having the above-described configuration, the position of the above-described paper holding spring 29 is fixed, so that the paper sensor 2
8 and the front seat guide lower 27b could not be automatically adjusted according to the paper thickness. For this reason, conventionally, when the thin paper is used and when the thick paper is used, the paper holding spring 29
0 differs from the force of pressing the front seat 0 toward the front seat guide lower 27b. Therefore, since the sheet cannot be pressed with a predetermined constant pressing force, the sheet is likely to flutter, and the fluttering of the sheet greatly affects the reading accuracy of the ID and the detecting accuracy of the leading edge of the sheet.

Further, the horizontal printer feeds cut sheets by feed rollers 6a and 6b and feeds the cut sheets.
a and 7b, and the paper 10 is fed by the feed rollers 6a and 7b by the feeding action of the feed rollers 7a and 7b.
Printing is performed up to the end of the sheet outside the positions a and 6b. Then, after the printing is completed, the sheet 10 may be fed in the reverse direction, fed again between the feed rollers 6a and 6b, and discharged to the operator side. When the paper 10 is fed in the reverse direction, the rear end face of the printing paper is
There is a drawback that the paper jams at the end of the sheet No. 9 and causes paper jam and breakage of the spring.

SUMMARY OF THE INVENTION In view of the above problems, the present invention improves the method of pressing a sheet in front of a sheet sensor so that the sheet flows smoothly, eliminates fluttering of the sheet, and improves the reading accuracy of the sheet sensor. The purpose is to let them.

[0008]

In order to solve the above-mentioned problems, a paper guide mechanism in a printer according to the present invention includes a feed roller for rotating a pair of rollers to convey a sheet along a predetermined sheet feeding route. a sheet sensor disposed on an extension of the shaft for fixing the one roller of the pair of rollers, together with covering the paper sensor in a state where the sensing area of the paper sensor is open, conveying the sheet conveyed by the feed rollers Seat gear placed at the root
At the position opposite the opening of the seat guide lower and the idler
And a pressing roller provided coaxially with a shaft for fixing the other roller of the pair of rollers, and having a diameter slightly smaller than that of the other roller.

[0009]

By using a pressing roller instead of a spring used as pressing means for pressing the paper against the paper sensor, the frictional resistance against the paper can be changed from sliding frictional resistance to rolling frictional resistance. The feeding is performed smoothly, and the fluttering of the sheet can be reduced. Further, a paper sensor is disposed on an extension of a shaft for fixing one of the pair of rollers constituting the feed roller, and a presser having a slightly smaller diameter than the other roller coaxially with the shaft for fixing the other roller. since the roller is disposed opposite to the paper sensor, when the space between the sheet guide lower and the pressing roller paper moves, the sheet is Shitoga
It will be transported smoothly without any resistance from the idroa .

FIG . 1 shows an embodiment of the present invention, in which a paper
Sectional view of a portion where the sensor 28 is provided, as viewed from the side,
FIG. 2 shows an embodiment of the present invention, in which the paper sensor 28 is arranged.
It is sectional drawing which looked at the provided part from the front. Figure 1
And As is apparent from Figure 2, in this embodiment, use
The paper 10 is placed in the sheet guide upper (the front sheet guide in the figure).
Door upper 27a) and seat guide lower (CFC in the figure)
While being guided between the lower seat guide 27b).
It is configured to send. This front seat guider
A paper pressing roller 30 is provided on the side of the
The fed sheet 10 is placed on the front sheet guide lower 27b side.
Can be pressed. The paper pressing roller 30 is coaxially mounted on the same shaft 40 as the feed roller 6a, and has a roller diameter slightly smaller than that of the feed roller 6a. Paper
The sensor 28 is configured to detect a feed
It is arranged on the extension of the shaft for fixing the roller 6b.
You. The sensing area of the paper sensor 28 is opened.
The front sheet so as to cover the paper sensor 28
A guide lower 27b is provided.
In the drawer 27b, keep the paper 10 transport route.
Has become.

The mounting position of the paper pressing roller 30 is the same as the position of the paper pressing spring 29 (see FIG. 6) mounted on the conventional horizontal printer, so that the paper pressing roller 30 also faces the paper sensor 28. The outer peripheral surface of the paper pressing roller 30 is on an extension of the reading position of the paper sensor 28. In other words, the position where the paper 10 is pressed by the paper pressing roller 30 and the reading position of the paper sensor 28 match.

In the paper guide mechanism of the horizontal printer according to the present embodiment, the cut sheet first passes through the cut sheet route 11 in FIG. 1 and reaches the front sheet guide lower 27b. Then, the sheet passes between the front sheet guide upper 27a and the front sheet guide lower 27b, and at the same time as the feed roller 6 sandwiches the sheet, the outer peripheral surface of the sheet pressing roller 30 rotates and presses and flows the sheet. . Then, the paper sensor 28 operates at the pressed position.

The feed roller 6 and the paper pressing roller 30
Are coaxial with each other, and at this time, the paper pressing roller 30 also moves upward according to the thickness of the paper 10,
Paper holding roller 30 and front sheet guide lower 27
The gap length δ between b and b is kept constant at any sheet thickness. In addition, the provision of the paper pressing roller 30 enables a smooth feeding method of “front insertion, front discharge”, which is generally performed in a horizontal printer. That is, as the paper fed by the feed rollers 6a and 6b is printed, the feed rollers 7a and 7b are printed.
After reaching the position (b), the paper is further fed by the feed rollers 7a and 7b, and then comes off the feed rollers 6a and 6b. Then, after printing is performed to the rear edge of the paper,
The paper feeding direction is reversed, and the feed rollers 6a,
This is a method in which the paper is fed between the holes 6b and discharged forward (hereinafter, this method is referred to as back feed).

At the time of the back feed, the sheet press spring 29 used conventionally has a high possibility of causing interference between the press spring 29 and the rear end of the sheet. By doing so, it is possible to effectively prevent a jam or damage to the spring due to interference. Also, the feed roller 6a
The rotation in the same direction as above also helps stabilize the paper feeding.

[0015]

According to the present invention, as described above, the paper is pressed against the paper sensor by using the paper pressing roller which rotates freely in the paper feeding direction. The conventional sliding friction resistance can be changed to rolling friction resistance. Therefore, it is possible to smoothly feed the paper while pressing the paper toward the paper sensor, and it is possible to prevent the paper passing in front of the paper sensor from wrinkling or floating. Can be prevented. Further, since the paper pressing roller rotates freely with the feeding of the paper, the paper can be prevented from being caught by the paper pressing roller when the paper is fed backward, and the back feed can be performed without any inconvenience. Becomes possible. Further, since the paper press roller is mounted coaxially with the shaft on which the feed roller is mounted, the arrangement position of the paper press roller can be automatically changed according to the paper thickness of the paper. Paper detection and ID reading can always be performed.

[Brief description of the drawings]

FIG. 1 is a side sectional view illustrating details of a sheet sensor unit according to an embodiment of the present invention.

FIG. 2 is a front sectional view for explaining details of a sheet sensor unit according to the embodiment of the present invention.

FIG. 3 is a side view illustrating a main configuration of the horizontal printer.

FIG. 4 is a plan view illustrating a main configuration of the horizontal printer.

FIG. 5 is a perspective view illustrating a configuration of a main part of the horizontal printer.

FIG. 6 is a side sectional view for explaining details of a conventional paper sensor unit.

FIG. 7 is a front cross-sectional view for explaining details of a conventional paper sensor unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Paper 11 Cut sheet route 27a Front sheet guide upper 27b Front sheet guide lower 28 Paper sensor 30 Paper press roller 40 Shaft δ Gap length

Continuation of the front page (56) References JP-A-5-24681 (JP, A) JP-A-4-38058 (JP, A) JP-A-60-46252 (JP, U) JP-A-5-9954 (JP) , U) (58) Field surveyed (Int. Cl. ⁶ , DB name) B41J 11/42 B41J 13/00-13/02

Claims (1)

(57) [Scope of request for utility model registration] A feed roller configured to rotate a pair of rollers to convey a sheet along a predetermined sheet feeding route; and a sheet disposed on an extension of a shaft for fixing one of the pair of rollers. A sheet sensor that covers the paper sensor in a state where the sensing area of the paper sensor is open, and is disposed on a conveyance route of the paper conveyed by the feed roller.
At a position facing the opening of the seat guide lower,
A paper guide for a printer, comprising: a pressing roller provided coaxially with a shaft for fixing the other roller of the pair of rollers, and having a slightly smaller diameter than the other roller. mechanism.