JPH0224176A - Printer - Google Patents

Abstract

PURPOSE:To prevent a folding tendency of printing paper with a simple mechanism by a method wherein curl of the printing paper is corrected with a curl repairing rod during printing and the curl repairing rod is retreated when printing is not performed. CONSTITUTION:When printing is performed, printing paper 3 is fed by a transfer means 22 while curl of the printing paper 3 is being corrected with a curl repairing rod 6. When printing is not performed, by causing the curl repairing rod 6 not to press the printing paper 3 by retreating the curl repairing rod 6 in a direction wherein pressing of the printing paper 3 is released with a retreat means 13, a folding peculiarity of the printing paper 3 when printing is not performed for a long time can be prevented, and stacking after printing and feeding can be normally performed.

Description

[Detailed Description of the Invention] [1 Already Required] A printer capable of preventing printing paper from curling with a simple mechanism, which is capable of retracting a curl removal rod from a curl correction position when printing is not being performed. A printer that prints with a print head while transporting printing paper supplied from a roll media supply unit and set between a platen member and a print head by a transport means, A curl removing rod is provided between the media supply section and the platen member, and wraps around and presses the printing paper supplied from the rolled media supply section to straighten the curl of the printing paper. The curl removing rod is equipped with a retracting means for retracting the curl removing rod in the direction of releasing the curl, and the curl removing rod corrects the curl of the printing paper while printing on the printing paper, and when printing is not performed, the curl removing rod is moved away by the retracting means. The configuration is such that it can be evacuated.

[Industrial application field]

The present invention relates to a printer such as a thermal printer used for facsimile (hereinafter referred to as FAX), and particularly to a printer that can retract a curl removal rod from a curl correction position when not printing.

2. Description of the Related Art In recent years, printers such as thermal printers that can produce relatively high quality printing have been widely used in FAX machines and the like, and rolled paper or rolled thermal paper has been widely used as printing media.

The smaller the diameter of the roll, the more the roll of printing paper becomes curled, and when it is cut and sent out after printing, it is not stacked properly in the stacker. Therefore, it is necessary to remove curls before printing. However, if printing is stopped for a long time with printing paper set, it will tend to curl in the opposite direction and will not accumulate properly, so it is desirable to have a mechanism to prevent this curling. It is rare.

[Conventional technology]

FIG. 5 is an internal side view of the thermal printer. As shown in the figure, a roll of thermal paper (hereinafter referred to as roll paper) 3a is fed from a paper supply section 4a between a line-type thermal head 1a and a platen roller 2a. supplied, spring 5a,
It is pressed against the platen roller 2a with a predetermined pressure by the thermal head 1a urged by the thermal head 5b. The platen roller 2a is connected to a motor M.

The thermal head 1a is equipped with resistive heating elements (not shown) arranged in a line across the width of the roll paper 3a, and when a pulse current is selectively passed through the resistive heating elements based on print data, a corresponding resistance is generated. The heating element generates heat to color the roll paper 3a and print.

A curl removal rod 6a and a guide plate 7 are provided between the paper supply section 4a and the platen roller 2a, and the paper supply section 4
The roll paper 3a supplied from the curl removal rod 6a
The platen roller 2 is corrected by the guide plate 7.
It is guided in the direction of a.

If the roll paper 3a has curls, the curls will remain on the document cut after printing, so they are corrected in advance. That is, roll paper 3
When a is printed and cut as described later and sent out as a document with curls attached, it is transferred to the stacker 10 due to the curls.
In extreme cases, subsequent documents sent from the output port 9 may become jammed, and especially when receiving documents unattended such as in the case of faxes, documents may fall from the stacker 10. Correction is performed because some problems occur and it is not easy to align the pages of the document.

Therefore, the roll paper 3a printed by the thermal head 1a is sent in the six directions of arrows by driving the platen roller 2a. When printing of one page is completed, the roll paper 3a is sent out to the cutter section 8, cut into a predetermined size by the cutter section 8, sent out from a delivery port 9 (not shown), and stacked on a stacker 10.

Thereafter, as the platen roller 2a rotates in the opposite direction, the leading end of the unprinted roll paper 3a is back-feeded in the direction of arrow B to the printing start position. When the roll paper 3a is bank fed to the print start position, printing of the next page is started.

[Problem to be solved by the invention]

According to the above-mentioned conventional method, in order to facilitate document management after printing and sending, the roll paper is decurled in advance by a curl removal rod and then fed to the platen roller.
If printing is stopped for a long time with the roll paper set, the roll paper that was pressed against the curl removal rod will curl in the opposite direction, causing the document to be sent out after printing. If the documents are not stacked properly in the stacker, or even if there is an abnormally stacked document, subsequent documents may not be stacked properly and may fall due to the stacking force. Particularly in the case of unattended reception printing, etc., there is a problem in that such abnormal accumulation further impedes document management.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printer that can prevent printing paper from bending with a simple mechanism.

[Means to solve the problem]

FIG. 1 shows a diagram of the principle of the present invention. In the figure, l is a print head, 2 is a platen member, 3 is printing paper, 4 is a roll-shaped medium supply section, 22 is a transport means, 6 is provided between the roll-shaped medium supply section 4 and the platen member 2, A curl removal rod 13 wraps and presses the printing paper 3 supplied from the medium supply unit 4 to straighten the curl of the printing paper 3. Reference numeral 13 indicates a direction from the position where the printing paper 3 is wound and pressed to the direction where the pressure is released. This is a retracting means for retracting the curl removing rod 6.

Therefore, during printing on the printing paper 3, the curl removing rod 6 corrects the curl of the printing paper 3, and when printing is not performed, the curl removing rod 6 is retracted by the retracting means 13.

[Effect]

When printing, the curl removal rod 6 corrects curls in the printing paper 3 while feeding it through the conveying means 22. When not printing, the evacuation means 13 moves the curl removal rod 6 to press the printing paper 3. By retracting in the direction of release and preventing the curl removal rod 6 from pressing the printing paper 3, it is possible to prevent the printing paper 3 from bending when not printing for a long time, and to prevent the curl removal rod 6 from pressing the printing paper 3. Stacking can be performed normally.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

The same symbols as in FIG. 4 indicate the same objects.

Further, in FIG. 2, parts corresponding to those in FIG. 1 are surrounded by a dashed line.

As shown in FIG.
The other end of the arm 11 is fixed to the shaft 12 of the torque limiter 13a. A boo IJ14 is fixed to the torque limiter 13a, and a bell eye 5 is hooked between the pulley 14 and a pulley 2o coaxial with the platen roller 2a. The platen roller 2a is a coaxial pulley 2
0 is connected to the motor M1 by a belt 21.

A presser roller 16 is provided below the curl removing loft 6b, and when the arm 11 rotates in the direction of arrow C, the curl removing rod 6b comes into contact with the presser roller 16 and serves as a rotation stopper. A press roller 16 presses and rotates the roll paper 3a hung on the side.

Further, a stopper 17 is provided above the curl removal rod 6b to stop the arm 11 at a predetermined angle when it rotates in the direction of the arrow.

With such a configuration, when the platen roller 2a rotates in the direction of the arrow E during printing operation, the pulley 14 rotates in the direction of the arrow C, and the arm 11 rotates in the same direction, causing the curl removal rod 6b at the tip to rotate in the same direction. presses the presser roller 16 via the roll paper 3a and stops. When the pressing force of the curl removing rod 6b reaches a predetermined value, the torque limiter 13a slips and the pulley 14 continues to rotate.

The curl of the roll paper 3a is corrected by a curl removal rod 6b, and the paper is supplied to the platen roller 2a.

When printing of one page is completed, the roll paper 3a is sent out to the cutter section 8, cut into a predetermined size, sent out from the delivery port 9, and stacked in the stacker 1o. Thereafter, as the platen roller 2a rotates in the direction of arrow F, the leading edge of the unprinted roll paper 3a is back-feeded to the printing start position, but as shown in FIG. As the arm 11 rotates, the arm 11 rotates in the same direction and is prevented from rotating by the stopper 17.

As the arm 11 rotates, the curl removal rod 6b separates from the presser roller 16, releases the curl removal pressure on the roller 3a, and retreats upward.

Further, the roller 4 rotates, and the torque limiter 13a slips when the torque exceeds a predetermined value, and continues to rotate until the platen roller 2a completes rotation in the reverse direction for backfeeding.

When the roll paper 3a is back-fed to the printing start position, printing of the next page starts and the platen roller 2a
rotates in the direction of arrow E, the arm 11 rotates in the direction of arrow C, and the curl removing operation by the curl removing rod 6b is performed in the same manner.

Also, when printing of all pages is completed, backfeeding is performed, and printing is stopped at the position where backfeeding is completed, so that the curl removal rod 6b is held at the upper position by stopping the torque limiter 13a.

A different embodiment is shown in FIG. Fig. 4 differs from the embodiment explained in Fig. 2 in that the arm is rotated by a plunger magnet throat (hereinafter referred to as PM) instead of a torque limiter, pulley, etc. as the evacuation means. be.

That is, as shown in FIG. 4, the curl removal rod 6b is attached to one end of the lever 11a with the midpoint as the fulcrum 17, and the other end of the lever 118 is attached to the PM 13b and the spring 1.
It is connected to 3c. In the normal state, the lever 11a is pulled by the spring 13c and retracted to the position shown by the two-dot chain line in the figure, and is rotated to the position shown by the solid line in the figure by the excitation of the PM 13b.

With this configuration, when not printing,
The curl removing rod 6b at the tip of the lever 11a is in the upper position and does not work to remove curls from the roll paper 3a.When printing, the lever 1 is moved by excitation of the PM 13b.
1a rotates downward, the curl removal rod 6b is positioned below, and the curl removal of the roll paper 3a is performed.

In this way, the roll paper 3a is decurled during printing, and when not printing, the curl removal rod 6b is retracted to release the pressure on the roll paper 3a.
It is possible to eliminate the tendency of the roll paper 3a to fold when printing is stopped for a long time, to make the stack normal after printing and sending, and to improve document management. Particularly, confusion of documents due to falling from the stacker 10, which occurs when printing by unattended reception, can be prevented.

Furthermore, although the above embodiments have been described using thermal paper in a thermal printer, the present invention can also be applied to roll paper in the case of a thermal transfer type.

Furthermore, different embodiments have been described using thermal paper in the case of a thermal printer, but they can also be applied to roll paper in the case of a thermal transfer type. Curl removal lower F
It can also be generally applied in the case of

Further, in the above example, the case where the rotationally driven platen roller 2a is used as a means for transporting the printing paper 3a is explained, but the printing paper 3a can be similarly applied to the case where the printing paper 3a is transported by other members 1 such as a feed roller.

[Effects of the Invention] As explained above, according to the present invention, when printing is not performed, the curl removal rod can be retracted so as not to press the printing paper in the curl removal direction. This has the effect that it is possible to prevent the printing paper from bending, and it is possible to perform printing and stacking correctly after sending out.

[Brief explanation of the drawing]

Fig. 1 is a diagram of the principle configuration of the present invention, Fig. 2 is a side view showing an embodiment of the invention, Fig. 3 is an explanatory diagram of the embodiment, Fig. 4 is a side view showing a different embodiment, Fig. 5 1 is a side view of a conventional thermal printer. In the figure, 1 is a print head, 1a is a thermal head, 2 is a platen member, 2a is a platen roller, 3 is printing paper, 3a is roll paper, 6.6a, 6b are curl removal rods, 13 is an evacuation means, 13a is Torque limiter, 1
3b indicates the PM, and 22 indicates a transport means. 77-L Goth 1 Noro Sodo 6 Sitting 40 Harajiri Oval Claw Diagram 1 True Heart August f7j Self I Row and Show 'TO'JΔoU Tsukasa Vine 2r
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Claims (1)

[Claims] While the printing paper (3) supplied from the roll-shaped medium supply section (4) and set between the platen member (2) and the print head (1) is transported by the transporting means (22). A printer that prints using the print head (1), the printer comprising: the roll medium supply section (4) and the platen member (
a curl removing rod (6) that is provided between 2) and wraps around and presses the printing paper (3) supplied from the rolled medium supply section (4) to straighten the curl of the printing paper (3);
and a retracting means (13) for retracting the curl removing rod (6) from a position where the printing paper (3) is wrapped around and pressed in a direction in which the pressure is released, and printing on the printing paper (3) is provided. Inside is the curl removal rod (6
) corrects the curl of the printing paper (3), and when printing is not performed, the printer is configured to retract the curl removing rod (6) with the retracting means (13).