JPH02202471A - Thermal transfer printing device - Google Patents

Abstract

PURPOSE:To dispense with a travel route for printing paper originating from outside the subject device and make possible the prevention of developed defects such as paper folds or jam by providing a head retraction mechanism which feeds and discharges roll paper due to its own rotation and at the same time, moves a printing head in response to a change in the diameter of the roll paper. CONSTITUTION:In printing data under a thermal transfer system, almost no impact generates during printing, so that it is possible to allow roll paper to take the place of a platen. As a progress is made in printing, the diameter of roll paper 12 becomes smaller gradually and the distance between the roll paper 12 and a printing head 13 becomes wider gradually. Then a head retraction mechanism 1 is adjusted so that its pressure is constantly maintained at a specified level. The head retraction mechanism 1 rotates a motor 2 as the diameter of the roll paper 12 becomes smaller gradually. Then a motor 2 is allowed to rotate and a drive force is transmitted to gear A3. At the same time, gear B4 rotates a cam 5 to transfer a pressing force to a transfer spring 7. Thus, the printing head 13 is allowed to come in contact with the roll paper 12 so that the pressure is not applied higher than a specified pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a thermal transfer printer device, and particularly to a thermal transfer printer device using roll paper.

FIG. 3 shows a conventional example.

Conventionally, in this type of printer device, printing paper was stocked outside the device and the paper was fed from there to the printing section. A case where roll paper is used as printing paper will be described below.

A paper feeding motor (not shown) rotates the platen 10, and a pressure roller 11 provided parallel to the platen 10 moves the printing roll paper 12 onto the platen 10.
0, the roll paper 12 was fed to a predetermined location by the frictional force, and the paper was discharged after printing. Therefore,
A guide is required to guide the roll paper 12 into the printer device from the outside, and when setting the roll paper 12, it is necessary to insert the paper so that the leading edge of the paper is exactly perpendicular to the platen 10. Furthermore, during printing, the print head 13 presses against the roll paper 12 to print, so the platen 10 supports the roll paper 12 from the back side to counteract the pressure.

[Conventional technology]

[Problems to be Solved by the Invention] In the conventional example described above, the paper placed outside the printer device is fed and discharged to the printing position by the frictional force generated by the pressure between the platen and the pressure roller. For this reason, a running route for the printing paper from the outside to the printing unit is required, and the structure of this part may put stress on the paper, or if the printing paper is distorted when set, wrinkles or jams may occur. This caused the inconvenience that a failure occurred.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal transfer printer device that improves the disadvantages of the prior art and prevents problems that occur on printing paper during printing.

[Means to solve the problem]

The present invention includes a thermal transfer print head that prints information from the outside, and a roll paper that is printed by this print head. Then, a method is adopted in which the print head is installed to face the roll paper, and the print head is equipped with a head retraction mechanism that moves the print head in response to changes in the diameter of the roll paper. This aims to achieve the above-mentioned purpose.

[For production]

In a typical printer device, roll paper is installed in the position where the platen is normally installed, and the roll paper is directly driven to rotate like the platen. The roll paper is placed exactly at the position where the print head prints. Therefore, when printing for - lines is completed, the motor rotates the roll paper so that the next line to be printed comes to the printing position. In thermal transfer printing, there is almost no impact during printing, so if the paper is rolled fairly tightly, roll paper can be used in place of the platen. As printing progresses and the diameter of the roll paper gradually decreases, a head retraction mechanism is activated to keep the print head in constant contact with the roll paper at a predetermined pressure.

[Embodiments of the invention]

Unlike impact-type printers, which print on print paper by applying an impact to a print ribbon, thermal transfer printers perform printing using thermal energy, so there is almost no impact on the print paper. In addition, because the mechanism is very simple, it can be used as a compact word processor, etc.
It is widely used because of its low price.

FIG. 1 shows an embodiment of the present invention. Here, the same reference numerals are used for the same constituent members as in the conventional example described above.

The embodiment shown in FIG. 1 includes a thermal transfer print head 13 for printing information from the outside, and a roll paper 12 on which the print head 13 prints. A print head 13 is installed to face the roll paper 12, and the print head 13 is equipped with a head retraction mechanism 1 that moves the pad 13 toward the printing in accordance with changes in the diameter of the roll paper 12. There is.

This will be explained in further detail. The roll paper 12 is transferred to the print head 1
3 is arranged so that the printing position is on the line connecting the print head 13 and the core 12A of the roll paper 12,
The print head 13 is always able to print at right angles to the surface of the roll paper 120. The head retraction mechanism 1 also includes a motor 2 and a gear A3 to which rotational force is transmitted by the motor 2, as shown in FIG.
It is composed of a gear B4 that transmits the rotational force of the gear A3, a cam 5 and a return spring 6 that are rotated by the rotational force from the gear B4, and a transmission spring 7 that is connected to the print head 13.

Next, the operation will be explained.

The roll paper 12 is installed at the position where the platen (10 in FIG. 3) is normally installed, and the roll paper 12 is directly rotationally driven like the platen. The roll paper 12 is placed exactly at the position where the print head 13 prints. Therefore, when printing for - lines is completed, a motor (not shown) moves the roll paper so that the next line to be printed comes to the printing position.
Rotate 2. Since there is almost no impact during printing when printing with a heat transfer margin, the roll paper 12 can be used in place of the platen as long as it is rolled fairly tightly. As printing progresses, the diameter of the roll paper 12 gradually becomes smaller. Therefore, the distance between the roll paper 12 and the print head 13 gradually becomes thicker.Therefore, a head retraction mechanism 1 is provided to always maintain a predetermined pressure. , as the diameter of the roll paper 12 gradually becomes smaller (as the diameter of the roll paper 12 becomes smaller),
Motor 2 is rotated to transmit driving force to gear A3, and gear A3 further rotates gear B4. Gear B4
The cam 5 is rotated to transmit a pressing force to the transmission spring 7, and the print head 13 is pressed against the roll paper 12 without exceeding a predetermined pressure.

When the roll paper 12 is used up and replaced with a new one, the motor 7 is further rotated to rotate the cam 5,
A tensile force is transmitted to the transmission spring 7 by the return spring 6 to separate the print head 13 from the roll paper 12. After setting a new roll paper 12, rotate the motor 7 again,
The print head 13 is brought into contact with the roll paper 12 at a predetermined pressure to perform printing.

〔Effect of the invention〕

As explained above, in the present invention, the roll paper is placed at the position where printing is to be performed by the print head, the roll paper itself is rotated to feed and eject the paper, and at the same time, a predetermined pressure is applied in response to changes in the diameter of the roll paper. Equipped with a hent retraction mechanism that moves the print head to maintain the print head. This eliminates the need for a running route for printing paper from the outside, making it an unprecedented thermal transfer printer that can prevent problems such as paper wrinkles and jams caused by the structure of this part. equipment can be provided.

[Brief explanation of the drawing]

FIG. 1 is an overall partial cross-sectional view showing one embodiment of the present invention, FIG. 2 is an explanatory view of a helide retraction mechanism, and FIG. 3 is a partial cross-sectional view showing a conventional example. 1...Head retraction mechanism, 1o...
...Platen, 12...Roll paper, 13...
...Print head. Figure 1

Claims (1)

[Claims] (1) A thermal transfer printer device comprising a thermal transfer print head for printing information from the outside and a roll paper on which the print head prints, the print head being installed opposite to the roll paper. A thermal transfer printer apparatus characterized in that the print head is equipped with a head retraction mechanism that moves the print head in accordance with changes in the diameter of the roll paper.