JPH0542355B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a printer, and more particularly to a printer provided with a cut sheet feed mechanism.

[Prior art]

One of the methods of feeding paper to a printer is a cut sheet feed method.

In this method, recording paper cut to a certain size is stacked in layers and stored in a cut sheet feeder.
This is a method that automatically feeds paper to the vicinity of the printer's platen in synchronization with the printer's operation during automatic paper feeding.

After the recording paper is fed from the cut sheet feeder to a predetermined position on the printer's platen,
By rotating the platen, the leading portion of the recording paper is set at the first printing position.

However, at this time, in the conventional method, the rear part of the recording paper remains in contact with the cut sheet feeder's discharge roller, or even if it is not in contact with the cut sheet feeder's discharge roller, it may be inside the cut sheet feeder's case or It remains in the paper feed tray. This state continues even if the printer starts printing.

As a result, after printing a few lines with the printer, you can go back to the previous line and erase it, or go back to the part that has already been printed.
When you print additional characters or feed the recording paper in the opposite direction, the recording paper moves in the opposite direction at the printer's platen section, but cannot move at the cut sheet feeder section because it is pushed by the ejection roller. . This causes "wrinkles,""folds," and "stains" on the paper.

This drawback becomes more noticeable as the amount of feed in the direction increases.

Furthermore, even if the trailing edge of the recording paper has already been ejected from the cut sheet feeder, if you feed the recording paper in the opposite direction, the recording paper may get stuck to a part of the case of the cut sheet feeder or the ejection roller Similarly, there may be wrinkles, creases, etc.
“Dirt” occurs.

When a cut sheet feeder is installed and you want to print on a recording paper of a size other than the one set in the cut sheet feeder, the recording paper is fed to the printer by manual feed. Even with the recording paper fed in this way, if you print up to a certain part and then feed it in the opposite direction, the trailing edge of the recording paper may get caught in the case of the cut sheet feeder, or it may wrinkle or fold as before. , “dirt”
occurs.

As mentioned above, in conventional printers with cut sheet feeders, feeding paper in the opposite direction causes creases, folds, stains, etc. on the stomach, so reverse feeding is not possible, and electronic printers The drawback was that many functions such as automatic deletion, return to the top, and advance printing of layouts could not be used.

〔the purpose〕

The present invention has been made to eliminate the above-mentioned drawbacks of the conventional printer, and an object of the present invention is to provide a printer configured so that reverse feed can be performed without causing wrinkles or the like.

〔Example〕

The details of the present invention will be explained below based on embodiments shown in the drawings.

FIG. 1 is an external view of a typewriter with a cut sheet feeder as an example of a printer to which the present invention is applied. In the figure, reference numeral a indicates the typewriter main body, and reference numeral b indicates the cut sheet feeder main body.

FIG. 2 shows a sectional view of the paper feeding mechanism of the typewriter and cut sheet feeder.

In Fig. 2, 1 is the discharge roller of the cut sheet feeder, 2 is the paper feed tray, 3 is the paper stacked on the paper feed tray, 4a and 4b are the outer cases of the cut sheet feeder, 5 is the discharge tray, 6a and 6b
1 is an optical paper sensor, 7 is a platen, 8 is a feed roller of a typewriter, 9 is a case of a typewriter, 10 is a paper pail, and 11 is a take-up roller.

Next, the automatic paper feeding operation will be explained.

FIG. 3 is a flowchart showing the sequence of automatic paper feeding operations.

First, when automatic paper feeding is to be performed, the paper sensor 6a detects whether recording paper has already been set between the platen 7 and the feed roller 8 in step S1. If recording paper is set, the platen 7 is rotated in the forward direction so that the recording paper is discharged onto the discharge tray 5 in step S2. If the recording paper is not set, the recording paper is set in step S3.

Next, the discharge roller 1 of the cut sheet feeder is rotated to feed the paper until it contacts the platen 7 and the feed roller 8. The amount of rotation of the discharge roller is set in advance so that the paper comes into convenient contact with the platen 7 and feed roller 8, and then the rotation amount is set in step S4.
After the ejection roller rotates, the paper sensor 6b detects paper, and if no paper is being fed, the step
Issue a warning in S5. In step S6,
The printer's carriage (not shown) is moved to the center of the paper, and the paper bail 10 is lifted up from the platen 7. Next, in step S7, the platen is rotated in the forward direction and the paper is wound around the platen.

The leading edge of the paper is the paper bail 10 and the platen 7.
Naba step has reached the point where it is caught between
In S8, paper veil 10 is placed on platen 7.
Lower it to the side.

It is assumed that the first printing position on the supplied paper has already been input and determined by an operator or the like.

Subsequently, in steps S9 and S10, the platen 7 continues to rotate in the forward direction until the paper sensor 6b can no longer detect the paper.

If paper is detected by the paper sensor 6b, the platen 7 is rotated in the opposite direction in step S11. FIG. 4 shows the state when paper is no longer detected by the paper sensor 6b. As can be seen from the figure, the paper 12 fed from the cut sheet feeder
The rear end is completely separated from the cut sheet feeder. When the platen 7 is rotated in the opposite direction, the rear end of the paper is fed in the opposite direction along the dotted line 13, and comes into contact with the cut sheet feeder case 4a. As shown in the figure, the paper exit part of the cut sheet feeder case is in the direction where 4b is inside the cut sheet feeder with respect to the path that would take if the rear end of the paper was fed in the opposite direction than 4a. It's crooked.

Therefore, when the recording paper 12 leaves the paper feed tray 3, the paper passes through the gap between the cases 4a and 4b, hits the back side of the output tray 5, and is guided toward the platen 7 and feed roller 8. .

Conversely, the feeder paper in the opposite direction from the platen 7 first hits the cut sheet feeder case 4b and advances along it, and then hits the case 4a.

The angle between the wall of the case 4a and the paper 11 is sufficient to guide the rear end of the paper 12 to the outside of the cut sheet feeder.

Therefore, even if the recording paper 11 is fed in the opposite direction, it does not return to the inside of the cut sheet, but is guided to the outside of the cut sheet, that is, to the manual feed side.

Furthermore, rotate the platen 7 in the opposite direction, and when the paper returns to the initial printing position, stop rotating and proceed to the step
At S12, return the carriage to the specified position.

The above operation completes automatic paper feeding when paper is fed from the cut sheet feeder.

In the embodiment described above, the presence or absence of recording paper is determined by the paper sensor 6a, but at the beginning of automatic paper feeding, the presence or absence of paper is determined by the paper sensor 6b, and the paper sensor 6b detects that there is no recording paper. If the platen 7 is sequentially rotated by a certain amount after detecting this, the recording paper is ejected to the ejection tray, so the paper sensor 6a becomes unnecessary.

Furthermore, in the embodiment described above, each time paper is fed,
Although the recording paper is completely taken out from inside the cut sheet feeder to the outside of the cut sheet feeder, reverse indexing may not be necessary at all during printing.

In this case, the operation of the embodiment wastes time and reduces the actual printing speed.

Therefore, when performing the reverse index operation for the first time after a new recording paper is supplied, perform the operation in the embodiment, take the recording paper out of the cut sheet feeder, and then perform the reverse index operation for the second time onwards. In such cases, these operations may be omitted.

Furthermore, depending on the type of printer, approximately 1 to 2
In some row reverse indexes, wrinkles do not occur on the recording paper due to sagging of the recording paper. In such a case, it would be more convenient if the operation as in the embodiment is performed only in the case of a reverse index of three or more rows, for example.

Even when the recording paper is fed manually with the cut sheet feeder attached to the typewriter instead of being fed from the cut sheet feeder, there is a step at the exit of the recording paper in the cut sheet feeder case. If the operation of the present invention is performed when an operator or the like instructs automatic paper feeding by attaching the
Since the recording paper passes through the path of the cut sheet feeder case, it is convenient because it does not cause "wrinkles" or "folds" on the recording paper.

As explained above, when the recording paper advances from the platen and feed roller of the printer, make sure that it does not enter the cut sheet feeder or get caught in a part of the case of the cut sheet feeder. A step is provided at the paper exit so that the printer can remove the fed recording paper from the cut sheet feeder at a glance before the printer needs to feed the paper in the opposite direction. Since the paper is guided to the manual feed side, there is no problem with the next paper feed in the opposite direction, just like when a conventional cut sheet feeder is attached.
It becomes possible to fully utilize the electronic functions of the electronic printer without impairing the electronic functions of the printer, and there is no need to add new parts and there is no cost increase.

[Effects] As is clear from the above description, according to the present invention, there is a cut sheet feeder that feeds cut sheets, a conveying means that conveys the cut sheets fed out from the cut sheet feeder, and a conveyance means that conveys the cut sheets fed out from the cut sheet feeder. control means for controlling the conveying means so that the conveying means conveys the cut sheet in the forward direction until it passes through an exit portion of the cut sheet feeder, and after passing through the cut sheet feeder, the conveying means conveys the cut sheet in the reverse direction; The cut sheet feeder includes a stepped portion formed at an exit portion of the cut sheet feeder to prevent the cut sheet, which is transported in the opposite direction by the transport means, from returning from the exit portion to the cut sheet feeder. ing.

Therefore, the cut sheet is conveyed in the forward direction until it passes through the outlet of the cut sheet feeder, and then the cut sheet is conveyed in the reverse direction. A means is provided to prevent the cut sheet from returning to the cut sheet feeder, so even if the cut sheet is conveyed in the opposite direction for the purpose of performing a printing function such as reverse index, the cut sheet will not return to the cut sheet feeder. It is possible to reliably prevent the sheet from becoming smeared by the stepped portion, and it is also possible to reliably prevent the sheet from wrinkles, folds, and stains, and it is fully equipped with various functions such as automatic erasing and advance printing. It can be used for

Furthermore, an extremely simple and inexpensive structure in which a stepped portion is formed at the exit portion of the cut sheet feeder has excellent effects such as being able to prevent sheets from returning.

[Brief explanation of the drawing]

The figure explains one embodiment of the present invention.
The figure is a perspective view of a typewriter with a cut sheet feeder, FIG. 2 is a longitudinal cross-sectional side view of the main parts of the cut sheet feeder and the paper feeding mechanism of the typewriter, and FIG. 3 is a flowchart showing the operation of the present invention. FIG. 4 is a longitudinal sectional side view of the main parts of the paper feeding mechanism in the case of reverse direction feed. 1...Ejection roller, 2...Paper feed tray, 3...
Recording paper, 4a, 4b... Part of the exterior of the cut sheet feeder, 5... Output tray, 6a, 6b...
Optical paper sensor, 7...platen (conveyance means),
8...Feed roller (conveying means), 9...Typewriter case, 10...Paper bail, 11
...Take-up roller.

Claims (1)

[Scope of Claims] 1: a cut sheet feeder that feeds cut sheets; a conveyor that conveys the cut sheets fed from the cut sheet feeder; and a conveyor that conveys the sheets fed from the cut sheet feeder into cut sheets. a control means for controlling the conveying means so that the cut sheet is conveyed in the forward direction until it passes through the exit portion of the feeder, and then the cut sheet is conveyed in the reverse direction by the conveyance means; A printer characterized in that the printer comprises a stepped portion that restricts a cut sheet, which is conveyed in a reverse direction by the conveyance means, from returning from the outlet portion to the cut sheet feeder. 2. A manual insertion section is provided between the cut sheet feeder and the output tray of the printer, allowing the cut sheet to be manually inserted toward the conveying means,
2. The printer according to claim 1, wherein the cut sheet conveyed in the opposite direction by the conveyance means is guided to the manual insertion section by the stepped portion.