JPH03218862A - Thermal transfer type recorder - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermal transfer type recording device used, for example, in a facsimile recording unit or a printer.

(Prior Art) As a conventional thermal transfer type recording device of this type, one described in, for example, Japanese Patent Application Laid-Open No. 45-84862 is known. This device uses a thermal head to press an ink sheet against a recording paper, and then changes the width of the pulse voltage applied to the head to vary the printing energy applied to the ink sheet, thereby adjusting the density of the transferred image. It is possible to adjust it appropriately.

(Problem to be Solved by the Invention) However, such conventional thermal transfer recording devices only had the function of simply adjusting the density of the transferred image, so the image transfer was performed using a multi-strike method. When an ink sheet, that is, an ink sheet that can be used repeatedly, is used, there is a problem in that it is not possible to obtain a stable image and use it many times. That is, when a multi-strike ink sheet is used, the density of the transferred image decreases as the number of times it is used increases, but if the printing energy is increased as described above,
It is possible to restore the density of the image. but,
When simply adjusting the density, you have to rely on visual inspection each time, and it is difficult to apply printing energy to the ink sheet that is appropriate for the number of times the ink sheet is used.Therefore, it is difficult to apply more printing energy than necessary. In addition, the number of times the ink sheet is used is often reduced, resulting in the above-mentioned problems.

(Object of the Invention) The present invention has been made against the background of the problems of the prior art as described above, and is achieved by providing a sensor that detects the number of times an ink sheet is used and a control means that controls the printing energy of a thermal head. An object of the present invention is to provide a thermal transfer recording device that can ensure stable images by changing the printing energy of a thermal head in accordance with the number of times an ink sheet is used, and at the same time can increase the number of times that an ink sheet is used. It is said that

(Structure of the Invention) In order to achieve the above object, the present invention provides a thermal transfer type recording device that presses a reusable ink sheet onto a recording paper using a thermal head and applies printing energy to transfer an image onto the recording paper. , a sensor for detecting the number of times the ink sheet is used, and a control means for controlling the printing energy of the thermal head, and the printing energy of the thermal head is changed in accordance with the number of times the ink sheet is used. That is.

Embodiments of the present invention will be described below based on the drawings. 1st
7 to 7 are diagrams showing an embodiment of a thermal transfer type recording device according to the present invention.

First, the configuration will be explained.

In FIG. 1, reference numeral 1 is an ink sheet cassette of the thermal transfer type recording device 2 in this embodiment, and the ink sheet cassette 1 includes a first roller 3 at the left end in the figure.
However, second rollers 4 are rotatably provided at the right end in the figure. When the second roller 4 is connected to a step motor 6 provided on the lower frame 5 and rotates, the ink sheet 7 wound around the first roller 3 is rotated.
is wound around the second roller 4, and the middle portion of the ink sheet 7 is guided by guide rollers 8 and 9 so that it runs horizontally. On the other hand, the code lO is a recording paper, and the recording paper 1
Although not shown, ink is supplied from a paper feeder between a platen roller 1l provided on the lower frame 5 and the ink sheet 7, and is driven by a platen roller 11 connected to a step motor 6 and rotated. The ink sheet cassette l runs toward the second roller 4 of the ink sheet cassette l while contacting the ink sheet 7. Furthermore, the recording paper 10 is separated from the ink sheet 7 which is rolled up upward by the second roller 4, supported by a pair of discharge ports 12, and discharged out of the system. Further, reference numeral 13 is a thermal head provided on the upper frame I4 facing the platen roller 11, and the thermal head 13, as shown in FIG. to press. Here, the above-mentioned ink sheet 7 is composed of the above-mentioned multi-strike ink sheet that can be used repeatedly, and the ink sheets 7 are stacked one on top of the other in order from the thermal navel T"13 side, as shown in FIG. It consists of a heat layer (PET layer) 15, an ink holding layer 16, and an ink control layer l7.Thermal head 13 is heated as described above through a heating element 18 provided at the end of the thermal head l3 on the ink sheet 7 side. As the ink sheet 7 is pressed against the recording pad 10, a pulse voltage is applied to the heating element 18 to generate heat, and thermal energy, that is, printing energy is applied to the ink sheet 7. At the same time, the ink retaining layer 16 of the ink sheet 7 is heated. The ink is melted, and further the melted ink moves to the recording sleeve 10 through the ink control layer 17, and an image 19 corresponding to the pulse voltage of the heating element 18 is transferred to the recording sleeve 10.

FIG. 4 shows the thermal transfer type recording device 2 in this embodiment.
4 is a block diagram of a control system that controls the printing energy of the thermal head l3 among the control systems of
In the figure, the aforementioned ink sheet cassette 1, thermal head 13, and heating element 18 are schematically shown as blocks. On the other hand, in FIG. 4, the reference numeral 2l is a sensor that detects the number of times the ink sheet 7 is used, and the reference numeral 22 is a sensor that detects the number of times the ink sheet 7 is used.
1 is a control section serving as a control means for controlling the printing energy of the thermal head 13, that is, the heating element 18 of the thermal head 13. These sensors 21 and control section 22
Of these, the sensor 21 consists of an optical sensor, and as shown in FIG. 1, it is attached to the middle part of the upper frame 14, and as shown in FIG. The reflective labels 31 to 34 are detected. Note that FIG. 2 is a plan view of the ink sheet cassette 1 from above with the upper frame 14 removed in FIG. If the cassette 1 is black, the reflective labels 31 to 33 are configured to be white. And in Figure 1,
While the ink sheet 7 wound around the first roller 3 is repeatedly transferred to the recording paper 10 by the thermal head 13,
When the bobbin is wound around the second roller 4 and the first roller 3 becomes an empty bobbin, the upper frame 14 faces the first roller 3.
An end sensor 23 provided on the ink sheet 7 detects an end mark provided on the ink sheet 7, stops the step motor 6, and at the same time displays a sign indicating that reversal is required. Along with this, the operator removes the ink sheet cassette 1 from the thermal transfer recording device 2 and removes the above-mentioned reflective labels 31 to 3.
4, for example, the reflective Rahel 31 is removed. moreover,
The ink sheet 7 is used repeatedly for the second time by mounting the first roller 3 and the second roller 4 in the thermal transfer recording apparatus 2 with their positions reversed. In this way, the first roller 3 and the second roller 4 are sequentially reversed and the ink sheet 7 is used repeatedly, and each time the reflective labels 31 to 34 are
Since the ink sheets 7 are removed one by one, the sensor 21 can detect the number of times the ink sheets 7 have been used. In addition,
In this embodiment, the number of times the ink sheet 7 is used is four, but it is of course not limited to this, and although the sensor 21 is described as being of an optical sensor type, it is not limited to this. However, other types of sensors, such as mechanical sensors, may also be used. Furthermore, when the positions of the first roller 3 and the second roller 4 are reversed as described above, the first roller 3 is connected to the stump motor 6 via a sliding clamp and is driven by the stoop motor 6. The ink sheet 7 wound around the second roller 4 can be wound up.

In FIG. 4, the aforementioned control section 22 is constituted by a microcomputer equipped with an A/D converter 24, an interface 25, a CPU 26, and a memory (ROM) 27. Note that the reference numeral 28 indicates the thermal head l3.
The heat generation temperature of the heating element 18 detected by the thermistor 28 is detected by the A/D converter 24.
The temperature information is converted into a digital signal and input to the CPLl 26 via the interface 25 as temperature information. Further, the number of times the ink sheet 7 has been used detected by the sensor 21 is sent to the computer via the interface 25 as number information.
It is input to PU26. Then, the CPU 26 sets the width of the pulse voltage to be applied to the heating element 18 of the thermal head 130 based on the table stored in the memory 27 from the above-mentioned temperature information and number of times information, and outputs it to the thermal head 13, so that the heating element 18 The printing energy applied to the sheet 7 is controlled. That is, in this embodiment, the control unit 22 is configured to change the printing energy of the thermal head 13 in accordance with the number of times the ink sheet 7 is used as detected by the sensor 2l.

Here, FIG. 5 shows a multi-strike ink sheet when the printing energy of the thermal head 13 is changed.
That is, it is a graph showing the relationship between the number of times the ink sheet 7 is used and the density of the transferred image l9 in this example. As shown in FIG. 5, when the printing energy of the thermal head 13 is large, the density of the transferred image 19 becomes high at the first time, but the density rapidly decreases as the number of times of use increases. Furthermore, when the printing energy of the thermal head l3 is small, the density of the image 19 decreases relatively slowly with respect to the number of uses. In FIG. 3, when the printing energy applied to the ink sheet 7 by the heating element 18 of the thermal head 130, that is, the thermal energy (mJoule) applied to the ink sheet 7 every 1 dot, is large, the ink is retained in the ink holding layer 16. This is because the amount of ink that passes through the ink control layer 17 increases.

Therefore, when the printing energy is thick, the amount of ink held in the ink retaining layer 16 of the ink sheet 7 that has completed the first transfer decreases, and the density of the next transferred image 19 decreases significantly. After repeated use, the ink in the ink holder J'316 dries up and the ink sheet 7 becomes unusable. There is no practical problem as long as the density of the image 19 transferred to the normal recording medium 10 is 1.0 (reflection density) or more, so in this embodiment, the control unit 22 controls the density of the image 19 to be 1.1 or more. It is controlled so that

Next, the effect will be explained. FIG. 6 is a graph showing the relationship between the number of times the ink sheet 7 is used and the printing energy controlled by the control unit 22 in this embodiment, and FIG. This is a graph showing the relationship between the density of the image 19, and the operation of this embodiment will be explained below based on FIGS. 1 to 7.

In FIG. 1, the step motor 6 of the thermal transfer recording device 2 is driven to rotate the second roller 4 of the ink sheet cassette l, and the ink sheet 7 wound around the first roller 3 is moved to the guide rollers 8, 9. Guided by
It is wound around the roller 4.

At the same time, the recording paper 10 is fed between the ink sheet 7 and the platen roller 11 rotated by the step motor 6, the thermal head 13 presses the ink sheet 7 against the recording paper 10 supported by the platen roller 11, and then the thermal head A pulse voltage is applied to the thirteen heating elements 18 . Then, the heating element 18 of the thermal head 13 generates heat and applies printing energy to the ink sheet 7, and as shown in FIG. The image 19 is transferred to the recording paper 10 . Then,
In FIG. 1, the recording paper 10 runs along the ink sheet 7, and the recording paper 10 that has been transferred to the outside of the thread by the discharge port 12
It is discharged as O. When the above-described transfer to the recording paper 10 is repeated and the ink sheet 7 is wound around the second roller 4, and the first roller 3 becomes an empty bobbin, the end sensor 23 detects the end mark of the ink sheet 7. Detect and second
The roller 4 stops, and at the same time, a sign indicating that reversal is required is displayed. Accordingly, the ink sheet 7 that has been used for the first time is removed from the thermal transfer recording apparatus 2 together with the ink sheet cassette 1 by the operator. Next, the reflection racks 31 to 34 shown in FIG. 2 of the ink sheet force sensor 1 are
Of these, the reflective roller 31 is removed, and the ink sheet cassette 7 is reinstalled with the first roller 3 and second roller 4 reversed.
1 is attached to the thermal transfer type recording device 2. In this way, the first roller 3 and the second roller 4 are sequentially reversed and the ink sheet 7 is used repeatedly, and each time the reflective sheets 31 to 34 are removed one by one. In FIG. 4, each time the ink sheet cassette 1 is reversed, the sensor 21
detects the number of times the ink sheet 7 has been used, and outputs it to the CPU 26 via the interface 25 as number information.

At the same time, the thermal head 13 detected by the thermistor 28
temperature information is input to the CPU 26 via the A/D converter 24 and the interface 25, and the CPU 26 determines the pulse voltage to be applied to the heating element 18 based on the table stored in the memory 27 from the input frequency information and concentration information. Set width. Therefore, the printing energy of the thermal head 13 is controlled each time according to the number of times the ink sheet 7 is used, and as shown in FIG. 6, the printing energy of the thermal head 13 increases with the number of times the ink sheet 7 is used.

As a result, as shown in FIG. 7, the density of the image 19 transferred to the recording paper 10 can clear the reference value of 1.1 or more up to four times. Therefore, it is possible to significantly increase the number of times the ink sheet 7 is used with stable images.

In this way, in this embodiment, since the sensor 21 that detects the number of times the ink sheet 7 is used and the control section 22 that controls the printing energy are provided, the thermal head 13 is controlled in accordance with the number of times that the ink sheet 7 is used. Print energy can be changed.

Therefore, it is possible to maintain a stable image 19 with the density of the image 19 on the recording paper 10 equal to or higher than the reference value, and at the same time, it is possible to increase the number of times the ink sheet 7 is used.

(Effects) According to the present invention, since a sensor for detecting the number of times the ink sheet is used and a control means for controlling the printing energy are provided, it is possible to change the printing energy of the thermal hand in accordance with the number of times the ink sheet is used. can. Therefore, it is possible to provide a thermal transfer type recording device that can ensure stable images, which is the object of the present invention, and at the same time can increase the number of times an ink sheet can be used.

[Brief explanation of drawings]

1 to 7 are diagrams showing an embodiment of a thermal transfer type recording device according to the present invention, and FIG. 1 is a front configuration diagram thereof;
Fig. 2 is a plan view of the ink sheet cassette, Fig. 3 is an enlarged view of the section ■ in Fig. 1, Fig. 4 is a block diagram showing the control section, and Fig. 5 shows the ink when the printing energy changes. A graph showing the relationship between the number of times the sheet is used and the density of the transferred image. Figure 6 is a graph showing the relationship between the number of times the ink sheet is used and the printing energy of the thermal hen. Figure 7 is a graph showing the relationship between the number of times the ink sheet is used and the density of the transferred image. 3 is a graph showing the relationship between image densities. 2... Thermal transfer type recording device, 7...
・Ink sheet, 10...Recording paper, 13...Thermal print, l9...Image, 21...Sensor, 22...Control (control means).

Claims (1)

[Claims] A thermal transfer recording device that presses a reusable ink sheet onto a recording paper using a thermal head and applies printing energy to transfer an image onto the recording paper, includes a sensor that detects the number of times the ink sheet is used, and a thermal head. control means for controlling the printing energy of the
1. A thermal transfer type recording device characterized in that the printing energy of the thermal head is changed according to the number of times the ink sheet is used.