JPH0354635B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a transfer type thermal recording device that uses an ink donor film itself as a thermal recording medium to transport recording paper, and particularly relates to The present invention relates to a transfer type thermal recording device that can accurately maintain a recording position.

"Prior Art" In a transfer type thermal recording device, image information is recorded by a thermal transfer recording method using a thermal recording medium called an ink donor film.

FIG. 5 shows an example of such a transfer type thermal recording device. In this transfer type thermal recording device, an ink donor film 11 is used as a thermal recording medium.
is fed out from a supply roll 12 wound into a roll, passed between a back roll (press roll) 13 and a thermal head 14, and between a drive roll 15 and a pinch roll 16, and then wound onto a take-up roll 17. It's getting old. This ink donor film 11 is conveyed by a drive roll 1 which receives driving force from a step motor 18.
5 is starting to do this. In this device, the recording paper 19 uses plain paper cut to a predetermined size. Recording paper 1 stacked on paper feed tray 21
The ink donor film 9 is fed out one by one by a feed roll (not shown) and is overlapped with the ink donor film 11 fed out from the supply roll 12. Then, in this superimposed state, they pass between the back roll 13 and the thermal head 14. At this time, the back roll 13 plays the role of pressing the recording paper 19 against the thermal head via the ink donor film 11. The thermal head 14 is a line-type recording head in which a large number of unit heating elements are arranged in a row in a direction perpendicular to the drawing, and these unit heating elements are selectively energized and heated according to image information to generate thermal pulses. to occur. At the portion of the ink donor film 11 to which the heat pulse is applied, the thermally transferable ink applied thereto is fluidized or sublimated, and is transferred onto the overlapping recording paper 19. In this way, thermal transfer recording progresses line by line.

The recording paper 19 that has passed through the thermal head 14 is then conveyed together with the ink donor film 11 and passes between a drive roll 15 and a pinch roll 16. At this time, the ink donor film 11
Since the recording paper 19 suddenly changes its traveling direction, the recording paper 19 cannot follow this and is peeled off, and is ejected to an ejection tray (not shown).

The outline of the apparatus that performs monochrome recording has been described above, but in this transfer type thermal recording apparatus, two-color or multicolor recording is also possible by arranging a plurality of recording sections on the conveyance path of the recording paper. As an example, FIG. 6 shows a two-color recording apparatus that records in two colors, black and red. Broken line 23 is recording paper 1
9, and the black recording section B is shown in this figure.
and a red recording section R are arranged. In each of the recording sections B and R, backroll 1 is stored in the same way as in FIG.
3B, 13R, thermal head 14B, 14R,
Drive rolls 15B, 15R, pinch rolls 16B, 16R, etc. are arranged. In the black recording section B, black ink is transferred onto the recording paper 19 by the black ink donor film 11B fed out from the supply roll 12B, and in the red recording section R, black ink is transferred onto the recording paper 19 by the red ink donor film 11R fed out from the supply roll 12R. The red ink is then transferred onto the recording paper 19.

``Problems to be Solved by the Invention'' Now, in such a transfer-type thermal recording device, a sensor is placed on the conveyance path of the recording paper to detect the passing state of the recording paper, and based on this, the drive start of the thermal head is determined. Deciding on the timing. However, with transfer-type thermal recording devices such as those shown in Figures 5 and 6, even if such technology is used, the recording position of the image may shift slightly depending on the usage environment, or the usage time of the product may be shortened. In many cases, the discrepancy became apparent over time. Particularly in the case of a two-color or multi-color recording device, this may cause color misregistration, which is a cause of deterioration of image quality. This misalignment of the recording position is caused by general factors such as a decrease in diameter due to the use of various rolls involved in conveying the ink donor film and recording paper, as well as rolls caused by wax applied to the ink donor film. At present, it has not been possible to make sufficient corrections due to the interplay of complex factors such as surface slippage and expansion and contraction of the recording paper and the ink donor film used as a carrier.

In view of these circumstances, it is an object of the present invention to provide a transfer type thermal recording device that can always accurately maintain the recording position on recording paper.

"Means for Solving the Problems" The present invention provides a thermal recording medium conveying means for conveying a thermal recording medium, a recording paper conveying means for conveying a recording paper, or both means, and a thermal recording medium conveying means for conveying a thermal recording medium or a recording paper conveying means for conveying a recording paper. a recording paper transport amount detection means for detecting the transport amount of the recording paper by the paper transport means;
A transfer type thermal sensitive device that performs recording by heating a thermal recording medium in accordance with recording image information, and a conveyance amount correction means that corrects the conveyance amount of the recording paper based on the detection result by the recording paper conveyance amount detection means. In the recording apparatus, the recording paper conveyance amount detection means includes a sensor that detects the reference image information when conveyance correction paper on which reference image information is written in advance is conveyed, and a reference that generates a reference signal corresponding to the reference image information. comprising: a signal generating means; and a comparing means for comparing the detection output of the sensor with a reference signal outputted by the reference signal generating means; and the correction amount of the conveyance amount correcting means is determined based on the comparison result of the comparing means. It is characterized by control.

With such a configuration, in the transfer type thermal recording apparatus of the present invention, fluctuations in the conveyance amount of the recording paper can be corrected at any time, and highly accurate conveyance control can be performed in accordance with the usage environment.

"Example" Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows the main parts of a transfer type thermal recording apparatus according to an embodiment of the present invention. Furthermore, the fifth
The same parts as in the figures are given the same reference numerals, and their explanations will be omitted as appropriate. Between the back roll 13 and the pinch roller 15 of this device, there is an optical sensor 71 for detecting the lightness and darkness of a minute portion at approximately the center position in the width direction of the recording paper, and a light source 72 that illuminates this detection area on the recording paper. A reflective photodetection device consisting of the following is attached. This reflection type light detection device is used to correct the conveyance amount of recording paper during maintenance and inspection of a transfer type thermosensitive recording device.

FIG. 2 shows a correction sheet used for correcting the conveyance amount of the recording sheet. This correction paper 74 is the same paper as the recording paper used for recording, but on its surface a ladder 75 is printed at predetermined intervals as reference image information. The correction paper 74 is sent out from a supply tray (not shown) and detected by the optical sensor 71 in a state where a service engineer or the like sets the transfer type thermal recording apparatus to the conveyance amount correction mode.

FIG. 3 is for explaining the conveyance amount correction operation using the detection output of this optical sensor. After the detection output 76 of the optical sensor 71 is shaped by a waveform shaping circuit 77, it is input to a pulse generator 78 consisting of a monostable multivibrator or the like, and a ladder detection pulse 79 corresponding to each thin line is obtained. The ladder detection pulse 79 is compared with a reference pulse 82 output from a reference pulse generator 81 by a comparator 83.
The reference pulse 82 is a pulse train of a constant frequency whose generation cycle matches the ladder detection pulse 79 when the correction paper 74 is conveyed at an ideal conveyance speed by the ink donor film 11 (FIG. 1). be. Comparator 83 is a phase comparator, and outputs a correction voltage signal 84 representing a correction voltage according to the phase difference between both pulses 79 and 82.

The correction amount determiner 85 A/D converts this correction voltage signal 84 and outputs it as correction data 86. This correction data 86 controls the period of the drive pulse 57 output from the motor driver 87, and the rotational speed of the step motor 55 is controlled.

The rotational speed of the drive roll 15 is changed by controlling the drive of the step motor 55. As a result, the transport speed of the ink donor film 11 changes, and the generation cycle of the ladder detection pulse 79 changes. That is, the generation cycle of the ladder detection pulse 79 is controlled to match that of the reference pulse 82. The correction amount determiner 85 determines the correction data 86 at the time when the conveyance speed of the correction paper 74 can be considered to have been completely corrected.
is stored in the built-in memory element. In this way, the correction operation ends. This stored correction data 8
6 is supplied to the motor driver 87 during normal recording operation, and is used to control the drive of the step motor 55.

In this embodiment, a correction sheet with one type of ladder printed thereon was used, but for example, as shown in FIG. By detecting this, it is also possible to control the conveyance amount with even higher precision.

In this way, according to the transfer type thermal recording device of this embodiment, the correction paper 74 on which reference image information is written is actually transported and the amount of transport is corrected, so that it can be used, for example, in a high humidity environment. Even in cases where transport is carried out, it is possible to easily perform highly accurate transport control according to the environment.

In the above embodiment, the conveyance amount was controlled by changing the frequency of the drive pulse, but it is also possible to adjust the conveyance amount by controlling the number of generated pulses or by controlling both of these. be.
Further, in the above embodiment, an apparatus for performing monochrome recording has been described, but it goes without saying that the present invention can also be applied to a multicolor recording apparatus.

"Effects of the Invention" As described above, according to the transfer type thermal recording apparatus of the present invention, since the conveyance amount of the recording paper is corrected using the conveyance amount correction paper on which reference image information is written, the ink donor Fluctuations in the conveyance amount of the recording paper caused by the film or conveyance rollers can be corrected at any time, and highly accurate conveyance control can be performed in accordance with the usage environment.

[Brief explanation of drawings]

Figures 1 to 4 are for explaining embodiments of the present invention, of which Figure 1 is a schematic configuration diagram showing the main parts of a transfer type thermal recording device, and Figure 2 is a diagram of the correction paper. A plan view, FIG. 3 is a block diagram of a circuit portion that corrects the conveyance amount, FIG. 4 is a plan view showing another example of correction paper, and FIG. 5 shows an example of a conventional transfer type thermal recording device. Schematic Configuration Diagram FIG. 6 is a schematic configuration diagram showing an example of a conventional two-color recording apparatus. 11... Ink donor film, 13... Back roll, 14... Thermal head, 15... Drive roll, 71... Optical sensor, 74... Correction paper, 75... Ladder (reference image information) 81...
...Reference pulse generator, 83...Comparator, 85...
Correction amount determiner.

Claims (1)

[Scope of Claims] 1. A thermal recording medium transporting means for transporting a thermal recording medium, a recording paper transporting means for transporting a recording paper, or both of these means, and a method for transporting recording paper by the thermal recording medium transporting means or the recording paper transporting means. The recording paper conveyance amount detection means detects the conveyance amount, and the conveyance amount correction means corrects the conveyance amount of the recording paper based on the detection result by the recording paper conveyance amount detection means, and corresponds to the recording image information. In a transfer-type thermal recording device that performs recording by heating a thermal recording medium, the recording paper conveyance amount detection means includes a sensor that detects the reference image information when conveyance correction paper on which reference image information is written in advance; a reference signal generation means for generating a reference signal corresponding to the reference image information; and a comparison means for comparing a detection output of the sensor with a reference signal outputted by the reference signal generation means; A transfer type thermal recording apparatus, characterized in that the correction amount of the conveyance amount correction means is controlled based on the result.