JPS63122571A - Printer - Google Patents

Abstract

PURPOSE:To enable high quality printing irrespective of the type of recording medium, by providing a means for detecting the mounting of a thermal transfer ribbon and a means for varying the printing pressure through a drive means. CONSTITUTION:When printing is made onto a thermosensible paper 4, an arm 7 is rotated slightly in the direction of an arrow C by a solenoid 8 so as to rotate a shaft 2, thus moving a thermal head 1 in the direction separating from the thermographic paper 4. When the solenoid 8 is opened at this time, the head 1 is pressed against the thermosensible paper 4 by the energizing force of a spring 5, thus making a print onto the thermosensible paper 4. When printing is made onto a plain paper, a ribbon cartridge 40 is fixed and a thermal transfer ribbon 14 is inserted between the head 1 and the plain paper. Upon mounting of the ribbon cartridge 40, a projection 17a of a detection lever 17 is pressed so as to rotate the detection lever 17 in the direction of an arrow D. Consequently, a variable lever 15 secured to a detection shaft 16 rotates in the direction of the arrow D, thus increasing the tensile force of the spring 5. As a result, a clear print can be made even onto a plain paper which conventionally requires a large printing pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a printing device, and particularly to an improvement of its printing al component.

[Prior Art] A connecting rod 12, a shaft 2, and a platen 3 are fixed to a side plate 10.11, which is shown in FIG. Thermal head 1 is carriage 2
0, and is configured to be movable along the shaft 2 by a moving device (not shown) (arrow A,
B) The thermal paper 4 is wrapped around the platen 3.
is inserted.

When performing a printing operation, the arm 7 is slightly rotated in the direction of arrow C by the solenoid 8.

Due to this rotation, the shaft 2 connected to the arm 7 also rotates at the same time, and the thermal head 1 is moved in a direction away from the thermal paper 4. At this time, the spring 5 is biased. When the solenoid 8 is released in this state, the head 1 is pressed against the thermal paper 4 by the biasing force of the spring 5. The head 1 is provided with a heat generating section, and the thermal paper 4 is heated and printed.

It is also possible to use plain paper instead of the thermal paper 4. In this case, as shown in FIG.
, and insert the thermal transfer ribbon between the head 1 and the plain paper as shown by the dashed line in FIG. By the same operation as described above, heat is applied to the thermal transfer ribbon 14 by the heating element of the print head 1, and the ink on the ribbon 14 is transferred to the plain paper.

[Problems to be Solved by the Invention] Conventional printing devices have the following problems. When printing on plain paper, clear printing cannot be achieved unless the printing pressure is increased.

That is, it is necessary to increase the tension of the spring 5. This is especially true when printing on rough paper with low smoothness. On the other hand, if printing is performed on thermal paper under high printing pressure, the thermal paper will be damaged, which is undesirable.Furthermore, as shown in FIG. There was a problem in that it adhered to the heating element 1a of No. 1 and changed the thermal response characteristics. In other words, a head that would normally have thermal response characteristics as shown by the solid line in Figure 6(A) will have its characteristics as shown by the broken line changed tenfold. )
As shown in the figure, the printing timing was off and the printing quality deteriorated.

An object of the present invention is to solve the above-mentioned problems and provide a printing device with excellent printing quality on both thermal paper and plain paper.

[Means for Solving the Problems] The printing device according to the present invention includes a detection means for detecting that a thermal transfer ribbon is attached, and also controls the pressure of the printing operation by the drive means in response to the detection by the detection means. Equipped with variable printing pressure means.

[Function] When the thermal transfer ribbon is attached, the detection means detects this, and the printing pressure variable means changes the printing pressure accordingly.
Appropriate printing pressure is set.

[Embodiment] Fig. 1 shows the structure of a thermal transfer printer according to an embodiment of the present invention.A connecting rod 12, a shaft 2, and a platen 3 are fixed to a side plate 10.11. The thermal head 1 is fixed to a carriage 20, and the thermal head 1 is fixed to a carriage 20.
In this embodiment, the carriage 20, the shaft 2, the arm 7, the solenoid 8, and the spring 5 constitute a driving means.

FIG. 3(A) shows a cross-sectional view of the vicinity of the carriage 20.
A head 1 is attached to the front surface of the carriage 20, and a shaft 2 passes through the center. An upper hole 20a is provided in the upper part of the carriage 20, and a protrusion 17a of the detection lever 17 protrudes from this upper hole 20. The detection lever 17 is fixed to the detection shaft 16, and rotation of the detection lever 17 is transmitted to the detection shaft 16. A variable lever 15 is fixed to one end of the detection shaft 16, and the lever 1 is adjusted as the detection shaft 16 rotates.
5 also rotates. A spring 5 is attached to the tip of the variable lever 15.

A case of printing on thermal paper will be explained. Platen 3
The thermal paper 4 is inserted so that it is wrapped around the paper. When performing a printing operation, the arm 7 is activated by the solenoid 8.
Rotate slightly in the direction of arrow C. Due to this rotation, the shaft 2 connected to the arm 7 also rotates at the same time.
The thermal head 1 is moved in a direction away from the thermal paper 4. At this time, the spring 5 is biased. In this state, when the solenoid 8 is released, the head 1 is pressed against the thermal paper 4 by the biasing force of the spring 5 □ The head 1 is provided with a heat generating part, and the thermal paper 4 receives heat and prints. .

Next, the case of printing on plain paper will be explained. In this case, as shown in FIG.
A thermal transfer ribbon is inserted between the head 1 and the plain paper as shown by the dashed line in FIG. When the ribbon cartridge 40 is attached, the protrusion 17a of the detection lever 17 is pressed as shown in FIG. 3(B), and the detection lever 1
7 rotates in the direction of the arrow. As a result, the variable lever 15 fixed to the detection shaft 16 rotates in the direction of the arrow, increasing the tension of the spring 5. Therefore, clear printing can be performed even on plain paper, which requires a large printing pressure.

In this embodiment, the detection lever 17a, the detection shaft 16
The variable lever 15 constitutes a detecting means, and the variable lever 15 constitutes a printing pressure variable means.

In another embodiment, a photoelectric element may be provided on the carriage 20 to serve as the detection means, and a solenoid that changes the tension of the spring 5 based on the output of the photoelectric element may be used as the variable means.

[Effects of the Invention] The printing device according to the present invention includes a detection means for detecting that a thermal transfer ribbon is attached, and a printing pressure variable means for changing the pressure of the printing operation by the drive means in accordance with the detection by the detection means. It is equipped with Therefore, it is possible to provide a printing device that appropriately selects the printing pressure depending on the type of recording medium and performs high-quality printing regardless of the type of recording medium.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the structure of a thermal transfer printer according to an embodiment of the present invention, FIG. 2 is a diagram showing the installed state of an ink ribbon cartridge, FIG. Figure 3 (B) is a sectional view showing the details of the carriage and its vicinity when an ink ribbon cartridge is installed, Figure 4 is a diagram showing the structure of a conventional thermal transfer printer, and Figure 5 is a diagram showing the structure of a conventional thermal transfer printer.
The figures show the details of the print head, Fig. 6 (A) shows the thermal response characteristics of the heating element of the print head, Fig. 6 (B) shows the print chart of a normal print head, and Fig. 6 (A) shows the thermal response characteristics of the heating element of the print head. Diagram (C)
1 is a diagram showing a print chart of a print head whose thermal response characteristics have changed due to adhesion of heat-melting paper powder. In the figure, 1 is a print head, 2 is a shaft, 3 is a platen, 5 is a spring, 7 is an arm, 8 is a solenoid,
15 is a variable lever, 17 is a detection lever, and 20 is a carriage. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) A platen, a thermal head for printing directly or via a thermal transfer ribbon toward a recording medium held on the platen, a detection means for detecting that the thermal transfer ribbon is attached, and printing on the thermal head. A printing device comprising: a driving means for performing the operation; and a printing pressure variable means for changing the pressure of the printing operation by the driving means in accordance with detection by the detection means. (2) The driving means includes a carriage that holds the thermal head, a shaft that rotates to enable the carriage to move back and forth with respect to the platen, an arm fixed to one end of the shaft, and a drive unit that is installed at one end of the arm and supports the thermal head. a drive solenoid for rotating the arm in a direction to move the thermal head away from the platen; and resilient means connected at one end to the other end of the arm for rotating the arm in a direction to move the thermal head closer to the platen; The means includes a detection lever protruding from the carriage, and the printing pressure variable means includes a variable lever that is connected to the other end of the elastic means and rotates in response to rotation of the detection lever. A printing device according to claim 1, characterized in that: