JPH11342641A - Paper-feeding method for color printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the paper-feeding method capable of printing an image longer than a head pitch without enlarging an apparatus. SOLUTION: In a paper-feeding method for a color printer for continuously printing an image longer than a recording part pitch on rolled paper P by three thermal heads HY, HM, HC, and first, second, third and fourth feed rollers 5, 6, 7, 8 corresponding thereto, the head of a printing area is matched with the corresponding thermal heads HY, HM, HC while the feed quantities of the respective feed rollers and the pass line of the paper P is changed between the feed rollers to perform printing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper transport method for a color printer, and more particularly to a paper transport method for a color printer capable of printing without being restricted by the length of an image.

[0002]

2. Description of the Related Art In a color printer such as a thermal transfer printer, the transport speed of paper tends to increase. However, the limit of the transport speed is limited to the characteristics (sensitivity) of the dye of the ink ribbon, the problem of wrinkling, the data transfer. Sublimation type 300DPI due to speed limitation and thermal head response speed limitation
In the case of, about 4.5 ms / line, 300 DP in the melting method
In the case of I, it is about 2.5 ms / line.

Conventionally, as shown in FIG. 5, a color printer equipped with a plurality of thermal heads for speeding up is known. In this printer, a single-color ink ribbon, specifically, a yellow ribbon Y, a magenta ribbon M, and a cyan ribbon C are arranged.
(Or long cut paper) is used.

The thermal head is a line-type head in which a number of heating elements are arranged in a line, and a sheet P sent from a roll sheet 1 moves in a direction indicated by an arrow in FIG. Thermal head (Thermal head H
Y, the thermal head HM, and the thermal head HC). Then, on the paper P, a yellow ribbon Y,
Ink is sequentially superimposed on the magenta ribbon M and the cyan ribbon C and transferred (melt heat transfer, sublimation heat transfer) to form a color image in one pass. A plurality of continuously recorded images are sequentially cut for each image by a cutter 3 arranged near a discharge port on the downstream side of the thermal head HC. Note that a paper guide 4 is arranged between the heads. This similar technique is described in, for example, JP-A-8-244262.

[0005]

However, in the above prior art, in order to cut a printed image one by one, it is necessary to interrupt the printing at image breaks. That is, if the printing is interrupted in the middle of printing an image, problems such as cooling of the ink and sticking to the paper P may occur.

Incidentally, in order to prevent useless blank space between images, as shown in FIG. 6, the print length (Lp) of one image and the pitch (Lh) of the head are in the following relationship. Need to be Lp = Lh / N (N is an integer of 1 or more, N = 2 in FIG. 6) Further, the pitch (Lct) between the cutter 3 and the head C and (Lct)
The relationship with p) is as follows. Lct = Lp × K (K is an integer of 1 or more) If Lct = Lh × 1, an image of an arbitrary recording length of Lh / N can be handled.

Here, as shown in FIG. 7, when the image length is longer than the head pitch and Lp> Lh, two images are always overlapped and recorded. Do not match, and no matter how the cutter 3 is arranged, it is necessary to temporarily interrupt the printing of one of the images. However, if the primary suspension is performed in this manner, as described above, a problem such as the ink being cooled and sticking to the paper occurs in the printing unit, and the problem that a linear printing failure along the head on the printed image appears. is there. Therefore, there is a limitation on the length of an image that can be printed depending on the head pitch, and the only way to increase the length of one printable image is to increase the head pitch, and there is a problem that an increase in the size of the apparatus is inevitable. Therefore,
SUMMARY OF THE INVENTION The present invention provides a paper transport method for a color printer capable of printing an image longer than the head pitch without increasing the size of the apparatus.

[0008]

In order to solve the above-mentioned problems, in the present invention, at least three recording sections are formed by using a roll-shaped sheet and an image longer than a recording section pitch by a corresponding conveying roller. Is a paper transport method of a color printer that continuously prints the print area by changing the paper path line between each transport roller by adjusting the transport amount of the transport roller corresponding to each recording unit, and changing the head of the printing area. The printing is performed by matching with the corresponding recording unit. With this configuration,
Even when the image length is longer than the recording unit pitch, the difference between the two lengths is absorbed and adjusted by changing the paper path line between the transport rollers.

A paper transport method for a color printer for continuously printing an image longer than a recording section pitch by using at least three recording sections and corresponding transport rollers using roll-shaped paper, comprising: Out to the most downstream, the first recording unit performs the first print of the first image while feeding the paper with the first transport roller of the first recording unit,
At the same time, the paper is fed by the transport rollers of the other recording units having a difference in the feed amount, and the first print of the second image is performed by the first recording unit while changing the paper path line between the transport rollers. The second printing of the first image is performed by the second recording unit, and then the first printing of the third image is performed by the first recording unit.
The printing is performed by the second recording unit, the second printing of the second image, and the third recording unit, by the third printing of the first image. The printing is performed while changing the pass line between the respective transport rollers of the sequentially fed paper. The head of the area may be matched with the corresponding recording unit and printed. here,
The recording section may be composed of a thermal recording head and a monochromatic ink ribbon. Also, by applying a tension corresponding to the paper path line to the paper retracted by changing the paper path line between the respective transport rollers, a constant tension is applied to the entire paper including the slackened portion. it can.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same parts as those of the prior art shown in FIG.

FIGS. 1 and 2 show a color printer according to an embodiment of the present invention. In FIG. 1, a color printer includes a roll paper 1 from an upstream side to a downstream side,
Paper feed roller 2, yellow ribbon Y as first recording unit, thermal head (hereinafter referred to as head) HY, platen R, first transport roller 5, magenta ribbon M as second recording unit, head HM , A platen R, a second transport roller 6, a cyan ribbon C as a third recording unit, a head HC, a platen R, and a third
The transport roller 7, the fourth transport roller 8, and the cutter 3 are sequentially arranged.

Here, between the first transport roller 5 and the head HM, between the second transport roller 6 and the head HC,
A paper guide 9 having a deep bottom which can be retracted by bending the paper P between the transport roller 7 and the fourth transport roller 8.
10 and 12 are provided. The pitch of each head is Lh, and the pitch Lct between the cutter 3 and the head HC is also equal to the head pitch Lh.

Next, a method for printing an image when the image length Lp is longer than the head pitch Lh by the color printer will be described. First, the paper P is fed out from the roll paper 1 until it reaches the fourth downstream transport roller 8, and the leading end of the paper P is sandwiched by the fourth transport roller 8. 4th above
After the leading edge of the paper P is nipped by the transport roller 8, the paper P is stretched to a constant tension (even in the width direction) by, for example, rotating the roll paper 1 in a rewinding direction via a torque limiter or the like. Then, the paper P is sandwiched between the first, second, and third transport rollers 5, 6, and 7.

Next, the heads HY, HM, HC, which have been retracted upward in preparation for the passage of the sheet P, are moved downward, and the sheet P is sandwiched between the corresponding platen R.
In this state, printing with the yellow ribbon Y is started. At this time, during printing, the speed (print speed Vp) Vry of the first transport roller 5 and the speed V
rm, the speed Vrc of the third conveying roller 7, and the speed Vrct of the fourth conveying roller 8 are set as follows. Vrm = Vry (= Vp) × Lh / Lp Vrct ≦ Vrc ≦ Vrm Here, the transport amount of each transport roller at the time of printing one image is:
The first transport roller 5 is Lp, the second transport roller 6 is Lh, the third transport roller 7 is Lp × Vrc / Vry,
The transport roller 8 is Lp × Vrct / Vry. Here, the head pitch is Lh and the image length is Lp.

When the speed of each transport roller is set as described above, the head of the printing area reaches the position of the head HM when the first printing of the first image by the yellow ribbon Y is completed. Can be matched to the head HM. Here, FIGS. 2 and 3
As shown in (a), Lh-L is applied between the heads HY and HM.
Since the pass line of the sheet P is lengthened by p, the surplus is curved and held by the sheet guide 9.
Next, the second print of the first image and the first print of the second image are performed. At this time, the speeds of the respective transport rollers are set in the following relationship. Vrm = Vry (= Vp) Vrc = vrm (= Vry = Vp) × Lx / Lp where Lx = ((Lh−Lp × Vrc / Vry) + Lh) = 2Lh−Lp × Vrc / Vry

As described above, when the speeds of the respective transport rollers are set, when the second print of the first image and the first print of the second image are completed, the heads of both print areas are just head HM. , HC, the heads of both print areas can be matched with the heads HM, HC. Here, as shown in FIGS. 2 and 3B,
Between the heads HY and HM and between the heads HM and HC. Since the path line of the sheet P is lengthened by the speed difference between the front and rear rollers, the surplus is held in a bent or curved state by the sheet guides 9, 10, and 12. Similarly, the third print of the first image, the second print of the second image, the third print
Also in the case of performing the first print of the image, as shown in FIG. 3C, the head of each image area reaches the position of each of the heads HM, HC, and the cutter 3 at the time of completion of each print. The transport speed of each transport roller is set so as to perform matching.

From the point of time when the third print of the first image, the second print of the second image, and the first print of the third image are completed, the speeds of the transport rollers 5, 6, 7, and 8 are uniform. Vp, and when the rear end of the first image (the head of the second image) reaches the cutter 3 when the process advances one step from the state of FIG. Cut P. After the cutting, the printing is restarted, and printing is performed on the paper P sequentially sent. Therefore, according to this embodiment, printing is possible even when the length of the image to be printed is longer than the head pitch.
In addition, since the head pitch may be short, the size of the apparatus can be reduced. By adjusting the transport speed of each transport roller and the timing of starting transport, an image of an arbitrary length can be printed. Of course, when printing an image whose image length is shorter than the head pitch, the paper P
Can be conveyed and printed without retreating.

Next, FIG. 4 shows an apparatus according to a second embodiment of the present invention. In this embodiment, in the paper guide 9, the paper P temporarily retracted between the first transport roller 5 and the second transport roller 6 (may be provided between other transport rollers). The guide rollers 11, 11, 11 apply tension in accordance with the paper path line. Therefore, by doing so, the tension of the paper P in the temporarily retracted portion can be maintained, and thus smooth conveyance of the paper P can be realized.

If the head of the printing area can be matched with each head by the speed difference between the respective transport rollers, the following method may be used. First, the first transport roller 5 is driven to start the first printing of the first image. At this time, the second, third, and fourth transport rollers 6, 7, and 8 are stopped. Next, when the first printing of the first image by Lp-Lh is completed, the second conveying roller 6 on the downstream side also starts driving at the same speed as the first conveying roller 5. In this way, there is a method of providing a difference in the drive start time of the transport roller. Further, the second transport roller 6 is stopped until the first printing of the first image is completed, and after the completion, the second transport roller 6 alone is driven in a state where the first transport roller 5 is stopped, and the paper P is transferred. The head of the printing area can also be matched to each head by a method that advances by Lh.

[0020]

As described above, according to the present invention, since each head can be arranged at a pitch shorter than the image length, there is an effect that the whole apparatus can be downsized. Also, since the image length is not determined by the head pitch, an image of an arbitrary length can be printed by adjusting the transport speed of each transport roller, the transport start timing, and the like, and the versatility can be improved. There is. When tension is applied to the sheet temporarily retracted between the transport rollers in accordance with the sheet pass line, the tension is unbalanced between the temporarily retracted portion and the other portion. Therefore, there is an effect that smooth conveyance of the paper can be realized.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an operation state of FIG. 1;

FIG. 3 is an explanatory diagram showing a printing situation according to time.

FIG. 4 is an explanatory diagram of an apparatus according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of an apparatus according to a conventional technique.

FIG. 6 is an explanatory diagram when the paper length is shorter than the head pitch.

FIG. 7 is an explanatory diagram when the paper length is longer than a head pitch.

[Explanation of symbols]

5 1st conveyance roller 6 2nd conveyance roller 7 3rd conveyance roller 8 4th conveyance roller 11 Guide roller Y Yellow ribbon (1st recording part) HY, HM, HC Thermal head (1st, 2nd, 3rd recording part) M Magenta ribbon (second recording unit) C Cyan ribbon (third recording unit) R Platen (first, second, third recording units) P paper

Claims (4)

[Claims] 1. A paper transport method for a color printer which continuously prints an image longer than a recording section pitch by using at least three recording sections and corresponding transport rollers using roll-shaped paper, comprising: A color printer that adjusts the transport amount of a transport roller corresponding to a recording unit to change the paper path line between each transport roller, and matches the head of the printing area to the corresponding recording unit for printing. Paper transport method. 2. A paper transport method for a color printer which continuously prints an image longer than a recording section pitch by using at least three recording sections and corresponding transport rollers using roll-shaped paper, comprising: To the most downstream, the first printing of the first image is performed by the first recording unit while the paper is fed by the first transport roller of the first recording unit, and at the same time another recording unit having a difference in the feeding amount. The first recording unit performs the first print of the second image by the first recording unit and performs the second print of the first image by the second recording unit while changing the paper path line between the respective conveyance rollers. First, the first recording section performs the first print of the third image, the second recording section performs the second print of the second image, and the third recording section performs the third print of the first image. A paper transport method for a color printer, characterized in that the head of a printing area is matched with a corresponding recording section and printing is performed while changing a pass line between transport rollers. 3. The method according to claim 1, wherein the recording unit includes a thermal recording head and a single-color ink ribbon. 4. The paper for a color printer according to claim 1, wherein tension is applied to the paper corresponding to a paper path line between the respective transport rollers. Transport method.