JPH0419165A - Thermal transfer recording apparatus - Google Patents

Abstract

PURPOSE:To make a complete transfer of ink possible according to an ink ribbon by equipping a printing synchronization reference signal generating means for specifying a printing interval suitable for each ink ribbon relative to plural sorts of ink ribbons and a means for converting the conducting time for a heating element in the manner of corresponding to each ink ribbon. CONSTITUTION:With the start of a printing operation, printing data are dot- developed from a printing data storage means 12 and inputted to a conducting time conversion means 2. The dot-developed printing data have an information showing whether power is applied to a heating element on a thermal head 10 and the data are converted into a conducting time most suitable for an ink ribbon set in a printer by the conducting time conversion means 2. Then, a head-driving circuit 7 conducts the heating element for the converted conducting time. CPU5 reads the period of a printing synchronization reference signal from an ink ribbon information storage means 4 for the purpose of determining a printing speed suitable for the set ink ribbon 21 and sets the period in a printing synchronization reference signal generating means 1. On the basis of this reference signal,the CPU5 drives a paper-conveying motor 8 and an ink ribbon-conveying motor 9 via a motor-driving circuit 6.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to a printing mechanism of a thermal transfer recording device.The present invention relates to a printing mechanism of a thermal transfer recording device. When printing a large number of printing dots, one
A method was used to realize this by considering it as one pixel.

FIG. 2 shows an example in which four printing dots are used to express four levels of density using the above-mentioned method of expressing density using area gradation.

On the other hand, a printing mechanism has been devised that expresses pixel density in gradation in units of printed dots by peeling off the ink ribbon from the paper while the ink remains in a molten state, and FIG. 3 is a conceptual diagram of this mechanism.

The ink 22 on the ink ribbon 21 is thermally melted by the heating element 20, and the thermally molten ink 25 comes into close contact with the paper 23 and the heating element 20, and then the ink 25 remains molten and is applied to the paper 23 at the end of the thermal head 10. The ink ribbon 21 is peeled off.

At this time, the amount of ink transferred to the paper 23 changes depending on the melted state of the ink 25.

[Prior Art] [Problems and Objectives to be Solved by the Invention] However, in the area gradation method using a large number of printed dots, the resolution must be reduced in order to realize high-resolution density gradation expression. For example, to reproduce an image comparable to a photograph, 256 levels of density gradation are required per pixel, but in order to achieve this, the vertical and horizontal resolution is reduced to 1/16, resulting in a rough image. Ta.

In addition, with the method of expressing density gradation for each printed dot by peeling the ink ribbon from the paper while the ink remains molten,
It is difficult to completely transfer the ink from the ink ribbon to the paper, so the performance of the ink ribbon, which was originally intended to completely transfer the ink to the paper, cannot be brought out, so the scope of application of the printing mechanism is limited to density. It was limited to printing with gradation expression.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to perform complete transfer of ink in accordance with an ink ribbon in a printing mechanism that realizes density gradation in units of printed dots.

[Means for Solving the Problems] In order to solve the problems, the thermal transfer recording device of the present invention includes a print synchronization reference signal generating means for defining a printing period suitable for each ink ribbon for at least two types of ink ribbons. The present invention is characterized by comprising means for converting the current application time to the heating element based on a conversion table corresponding to each ink ribbon.

[Function] The ink on the ink ribbon is thermally melted for an energization time set to generate sufficient adhesion to the paper, and then the ink is cooled and solidified during transportation when the ink ribbon and paper are peeled off. This allows complete transfer of the ink to the paper.

[Example] An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a thermal transfer recording apparatus of the present invention.

Print data is input from the outside and print data storage means 12
temporarily memorized.

At the start of the printing operation, the print data is expanded into dots from the print data storage means 12 and inputted to the energization time conversion means 2.

The print data developed into dots has information indicating whether or not the heating element on the thermal head 10 is energized, and the energization time conversion means 2 converts it into the optimum energization time for the ink ribbon set in the printing device. be done.

The head drive circuit 7 energizes the heating element on the thermal head 10 for the energization time converted by the energization time conversion means 2 .

The thermal head 10 and its surroundings are constituted by a printing mechanism shown in FIG.

When setting the ink ribbon 21, the ink ribbon recognition means 11 outputs a code indicating the type of ink ribbon depending on the state of the ink ribbon selection switch 3, and the CPU 5 recognizes the type of the ink ribbon 21 set.

Further, in order to determine a printing speed suitable for the set ink ribbon 21, the CPU 5 reads out the period of the print synchronization reference signal from the ink 1 nozzle information storage means 4, and sets it in the print synchronization reference signal generation means.

Based on the print synchronization reference signal, the CPU 5 drives the paper conveyance motor 8 and the ink ribbon conveyance motor 9 via the motor drive circuit 6. When the cycle of the print synchronization reference signal is long, the CPU 5 rotates the paper transport motor 8 and the ink ribbon transport motor 9 slowly, and when the cycle of the print synchronization reference signal is short, the CPU 5 rotates them quickly. Therefore, the cycle of the print synchronization reference signal is adjusted. The printing speed is controlled by .

Let L be the distance between the heating element 20 and the end of the thermal head 10 in the conceptual diagram of the printing mechanism shown in FIG.

If T is the time required for the ink on a certain ink ribbon to cool and solidify on the paper after it leaves the heating element, then the maximum printing speed V can be determined from the following equation.

V=L/T The ink ribbon information storage means 4 stores the period of the print synchronization reference signal that determines the maximum print speed (■) for each ink ribbon.

On the other hand, in order to transfer ink to paper, it is necessary to melt the ink until it soaks into the paper and provides sufficient adhesive strength.

However, as the printing speed differs depending on the ink ribbon as mentioned above, some ink ribbons may not have sufficient energization time.
Other ink ribbons may not be sufficient.

Therefore, in order to obtain the optimum energization time for each ink ribbon, the energization conversion means 2 converts it into the optimum energization time for each ink ribbon.

Since the energization time needs to be determined in units of printed dots, the energization time conversion means 2 is a ROM that does not require much conversion processing time.
Use.

FIG. 4 is a configuration diagram when a ROM is used as the energization time conversion means 2.

When inputting the address of the energization time conversion means 2, the print data indicating the printing density of the printed dots, the ink ribbon selection code from the ink ribbon recognition means 5, and the code indicating the printing conditions from the CPU 5 are used to calculate the optimum energization time of the printed dots. Extract the code shown from the data output.

[Effects of the Invention] With the mechanism described above, the thermal transfer recording device of the present invention can print with density gradation and completely transfer ink from the ink ribbon using the same mechanism by changing the printing speed and energization time. Since it is possible to carry out printing with a wide range of applications, it is possible to provide a printing mechanism that can be used in a wide range of applications depending on the ink ribbon.

[Brief explanation of the drawing]

4. Brief Description of the Drawings FIG. 1 is a block diagram of the thermal transfer recording apparatus of the present invention. FIG. 2 is a conceptual diagram showing a method of expressing density by area gradation. FIG. 3 is a conceptual diagram of a thermal transfer printing mechanism that realizes density gradation. FIG. 4 is a configuration diagram when a ROM is used as the energization time conversion means. 109. Print synchronization reference signal generation means 21. , energization time conversion means 408. Ink ribbon information storage means 12,...Print data storage means

Claims (1)

[Claims] In a thermal transfer recording device that has a thermal head and thermally melts ink on an ink ribbon and transfers it to paper, a print synchronization reference signal is generated for at least two types of ink ribbons to define a print cycle suitable for each ink ribbon. A thermal transfer recording device characterized by comprising means for converting the energization time to the heating element based on a conversion table corresponding to each ink ribbon.