JPS61189974A - Ribbon cartridge of thermal transfer printer - Google Patents

Abstract

PURPOSE:To realize high grade printing quality generating no printing omission or contamination by correcting the non-uniformity of tension in an orthogonal direction and eliminating the skew of an ink ribbon or winding disturbance, by supporting a guide roller for guiding an ink ribbon in a state rotatable and tiltable on the rotary center axis thereof. CONSTITUTION:At the time of printing operation, the ink ribbon 5 delivered from an ink ribbon pan cake 1 and guided by a guide roller 3 is fed while pressed to recording paper between a thermal head and a platen roller under pressure and taken up by a take-up core 2 but inclined to the direction shown by an arrow A with respect to the rotary center O of the guide roller 3 corresponding to the non-uniformity of tension in the direction at right angles to the running direction of the ink ribbon 5 generated at the time of taking-up and the distance between the rotary center axis Z-Z' and the outer periphery of the guide roller contacted with the ink ribbon is changed along the direction of the rotary center axis Z-Z' corresponding to the non-uniformity of tension in the direction orthogonal to the running direction of the ink ribbon and, by this mechanism, the non-uniformity of tension is corrected.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a ribbon cartridge for a thermal transfer printer.
In particular, it relates to the structure of an ink ribbon guide roller.

[Conventional technology]

Conventionally, this type of ribbon cartridge, as shown in FIG.
, guide rollers 3a, 3b, 3c, 3d, and a cartridge case 4. Here, the guide roller 3a*
3b+3c and 3d have a structure that rotates as the ink ribbon 50 runs in order to reduce the frictional resistance as much as possible when the ink ribbon 50 runs.

[Problem that the invention seeks to solve]

The conventional ribbon cartridge described above has a guide roller 3.
In many cases, a, 3b, 3c, and 3d are molded from a rigid body such as ABS resin, and have a structure that performs only a rotation function about a single axis. For this reason, when the recording paper and the ink ribbon are pressed between the platen roller and the thermal head during printing, the ink ribbon rewinds 7. The parallelism of each of the winding axis, the guide roller rotation axis, the thermal head pressing surface, etc. may be distorted. No, the unevenness of the tension balance in the direction perpendicular to the running direction of the ink ribbon, which occurs due to reasons such as partial thermal contraction of the ink ribbon due to heat generated during printing, or local changes in the thickness of the ink ribbon due to ink transfer, etc. I didn't have the ability to correct it. Therefore, this uneven tension balance of the ink ribbon causes skew of the ink ribbon, irregular running due to irregular winding, etc., resulting in missing prints, stains on the recording paper due to the recording paper/ink ribbon slipping, etc. There was a serious drawback.

The present invention provides a ribbon cartridge that eliminates printing defects and recording paper stains due to recording paper/ink ribbon slipping.

[Means for solving problems]

The ink ribbon cartridge of the present invention rotatably and tiltably supports a guide roller on its rotation center axis for guiding an ink ribbon stretched in the moving direction of the carriage facing recording paper, and It is characterized in that the distance between the rotational center axis and the outer periphery is changed along the guide roller rotational center axis direction depending on the uneven tension in the direction perpendicular to the running direction of the ink ribbon.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

As shown in FIG. 2, the ink ribbon 5 fed out from the ink ribbon cake 1 is attached to a guide roller 3a.

3b + 3c H3d and wound around the winding core 2.

FIG. 1 is a detailed sectional view of the guide roller in the present invention. In FIG. 1, a bearing 6 having a spherical concave surface is provided in the guide roller 3 and is positioned on the rotation center axis Z-Z', and the tip 7a of the force guide stud 7 is formed into a spherical shape.
The tip 7a of the stud 7 is fitted into the bearing 6 of the guide roller 3, so that it can rotate about the rotation center axis z-7 and can tilt within a predetermined range that is also in the direction of the arrow with respect to the rotation center O. The guide roller 3 is supported by the guide stud 7. The present invention applies the structure of the guide roller 3 shown in FIG. 1 to each of the guide rollers 3a to 3d shown in FIG. It was changed according to.

In the embodiment, during the printing operation, the ink ribbon 5, which is fed out from the ink ribbon cake 1 and guided by the guide roller, is pressed together with the recording paper between a thermal head (not shown) and a platen roller, while responding to the movement of the carriage. The guide roller 3 moves in the direction of the arrow A with respect to the center of rotation O in response to the uneven tension in the direction perpendicular to the running direction of the ink ribbon 5 that occurs at this time. The distance between the rotation center axis z - z' and the outer periphery of the guide roller in contact with the ink ribbon is adjusted along the rotation center axis z - z' force direction according to the uneven tension in the direction perpendicular to the running direction of the ink ribbon. [Effects of the Invention] As explained above, the present invention is capable of changing the distance between the rotation center axis of the guide roller that guides the ink ribbon and the outer periphery of the guide roller. By making it adjustable in the axial direction, it corrects uneven tension in the direction perpendicular to the ink ribbon's running direction, eliminates ink ribbon skew, uneven winding, etc., and achieves high quality printing without missing or smudging prints. There is an effect that can be done.

[Brief explanation of drawings]

FIG. 1 is a detailed sectional view showing a guide roller in the present invention, and FIG. 2 is a perspective view showing the configuration of a ribbon cartridge. 1... Ink ribbon pancake 2... Winding core 3.3a-3d... Guide roller 4...
・Cartridge case 5...Ink ribbon 7・
...Guide stud patent applicant NEC Corporation Figure 1

Claims (1)

[Claims] (1) A carriage equipped with a thermal head is moved back and forth in parallel with the platen, and during the reciprocation, multiple heating elements of the thermal head are selectively energized to generate heat based on printed information, thereby thermally melting one side of a base material such as PET. In a serial type thermal transfer printer, which melts the hot-melt ink on an ink ribbon coated with ink and transfers it to recording paper, an ink ribbon stretched in the direction of movement of a carriage facing the recording paper is guided. A thermal transfer printer characterized in that a guide roller is rotatably and tiltably supported on its central axis of rotation, and the distance between the central axis of rotation and the outer periphery of the guide roller is varied along the central axis of rotation. ribbon cartridge.