JPS62294564A - Printing mechanism - Google Patents

Abstract

PURPOSE:To improve a print quality of a fine point and to prevent a transfer of ink to a rubber roller and a twining of a print ribbon by preheating a head by a head preheating circuit and heating a return path electrode contacting with a wound print ribbon by means of said current and the current from a head drive circuit. CONSTITUTION:A print head 1 has been heated prior to the start of printing by feeding current to a ribbon 3a from a head preheating circuit 2 and the printing is performed by the current fed from a head drive circuit 4. After printing, a ribbon 3b is fed by means of a ribbon feed roller 5 and a rubber roller 6 so as to be wound on a pulley 8 through a return path electrode 7b. Here, the electrode 7b is moved from the position 7a to the position 7c by the ribbon 3c wound on a pulley 8 and contacts continuously with a constant pressure to the surface of the wound ribbon 3c. The electrode 7b serves as a return path of current from the circuit 2 and the head drive circuit 3 and the heat produced therein fuses the ink remaining on the ribbon 3b thus transferring or melt-adhering the ink onto the wound ribbon 3c.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a printing mechanism of an electric thermal transfer printer, and particularly to a method for improving printing quality and preventing airtight leakage of printed text11)
The present invention relates to a printing mechanism of an electric thermal transfer printer.

[Prior Art] Conventionally, as a printing mechanism of this type of energized thermal transfer printer, there is, for example, one shown in FIGS. 2(a) and 2(b).

In the figure, 11 is a head drive circuit, 12 is a print head, 13 is a print ribbon, 14 is a return electrode, and 15 is a rubber roller. Printing was performed by passing a current to the return electrode 14.

FIG. 2(b) shows the state 5E of the printing ribbon 13 after printing.
7E, in which the characters after printing remain on the printing ribbon 13.

[Problems to be solved] In the conventional printing mechanism described above,
1, printing was carried out by passing current through the print head 12 from the print ribbon 13 to the rubber roller 15 and further to the return path electrode 14 facing the rubber roller 15, resulting in poor printing quality of fine points due to ink transfer to the rubber roller 15. Or the wrapping of the printing ribbon 13, the printing ribbon 1 after printing.
3 has drawbacks such as the printed text leaking confidential information.

[Means for Solving Problems] The present invention has been made by focusing on the above-mentioned conventional problems, and improves the printing quality of fine points, transfers ink to the rubber roller, and prevents the printing ribbon from becoming entangled. Moreover, it is an object of the present invention to provide a printing mechanism that can prevent confidential information from leaking from the printing ribbon after printing.

To this end, the present invention provides a printing mechanism for an electrical thermal transfer printer that includes a head drive circuit for driving the print head, and a head preheating circuit that warms the print head by applying current to the print ribbon before printing starts. The present invention provides a printing mechanism characterized by comprising a return electrode which always moves in contact with the printing ribbon wound up after printing and which generates heat by the current from the head drive circuit and the residual heat circuit.

[Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is an explanatory diagram showing a printing mechanism according to an embodiment of the present invention.

In the figure, 1 is the print head, 2 is the head preheating circuit, 3a, 3b
, 3c is a printing ribbon, 4 is a head drive circuit, 5 is a ribbon feed roller, 6 is a rubber roller, 7a, 7b, 7c are return electrodes, 8 is a ribbon take-up pulley, and 9 is a printing paper.

The print head 1 is warmed by the head preheating circuit 2 by passing a current through the print ribbon 3a before starting printing, and prints by the current from the head drive circuit 4.

After printing, the print ribbon 3b is sent by the ribbon feed roller 5 and the rubber roller 6, and is wound around the ribbon take-up pulley 8 via the return circuit 8i7b. Depending on the thickness of the printing ribbon 3C wound around the ribbon take-up pulley 8, the return wire 8i7b moves to the position 7a or 7C, so that it always applies a constant pressure to the surface of the wound printing ribbon 3c. are in contact with each other.

The return electrode 7b serves as a return path for the current from the Rad preheat circuit 2 and the head drive circuit 3, and the heat generated here melts some of the ink or base material remaining on the printing ribbon 3b, and melts the ink or base material that has already been wound. The print ribbon 3c is transferred or welded onto the print ribbon 3c.

Therefore, it is possible to improve the printing quality of fine points, transfer the ink to the rubber roller 6, prevent the printing ribbon from being tangled, and prevent leakage of confidential information from the printing ribbon after printing.

[Effects of the Invention] As described in Section 1 below, the present invention provides a head drive circuit for driving the print head in the printing mechanism of a typical iR thermal transfer printer, and a method in which a current is applied in advance to the print ribbon before the start of printing. A head preheating circuit that warms the print head by heating the printing head, and a return electrode that is always movable in contact with the printing ribbon that is wound up after printing and that generates heat by the current from the head drive circuit and the preheating circuit. Because of this unique printing mechanism, the head is preheated by the head preheating circuit, and the current from the head preheating circuit and the current from the head drive circuit generate heat in the return electrode that is in contact with the wound printing ribbon, making it possible to print fine points. This has the effect of improving printing quality, transferring ink to the rubber roller, preventing the printing ribbon from becoming entwined, and preventing leakage of confidential information from the ribbon after printing.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing a printing mechanism according to an embodiment of the present invention, and FIG. 2 is a diagram showing a conventional printing mechanism. FIG. b) is an explanatory diagram showing the state of the printing ribbon after printing. ■ = Print head 2 Second preheat circuit 3a, 3b, 3c: Print ribbon 4: Head drive circuit 7a, 7b, 7c: Return electrode

Claims (1)

[Claims] In the printing mechanism of an electric thermal transfer printer, there is a head drive circuit for driving the print head, a head preheating circuit that warms the print head by passing current through the print ribbon before printing starts, and a print ribbon that is wound up after printing. 1. A printing mechanism characterized by comprising a return electrode which is always movable in contact with the head drive circuit and which generates heat due to the current from the head drive circuit and the residual heat circuit.