JPH0653433B2 - Thermal printer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention uses thermal printing in which a coloring pulse is projected from a thermal head to directly print on thermal paper and thermal transfer ribbon coated with a heat-meltable ink. A thermal printer that can perform thermal transfer printing, which prints on plain paper, as desired, detects whether the thermal transfer ribbon cassette is mounted or not mounted and detects the ribbon end of the thermal transfer ribbon. The present invention relates to a thermal printer having a mechanism.

Conventional technology In conventional thermal printers, thermal printing is performed by directly contacting the thermal head with thermal paper to print directly, and thermal transfer is performed by printing on plain paper using a thermal transfer ribbon coated with hot-melt ink. There is one in which printing can be arbitrarily selected to print on both thermal paper and plain paper. Here, the thermal energy applied to the thermal head is different between the thermal printing and the thermal transfer printing due to the difference in the coloring temperature between the thermal paper and the thermal transfer ribbon. Therefore, a device for detecting whether or not the thermal transfer ribbon cassette is mounted is required as a means for distinguishing the thermal transfer printing from the thermal transfer printing. As shown in FIG. 7, the detection of whether the thermal transfer ribbon cassette is mounted or not mounted is provided with a thermal head 3 and a ribbon take-up spool 4 which press the thermal paper or plain paper 1 against the platen 2 for printing. A mechanical switch 6 is provided on the carriage 5, and a thermal transfer ribbon cassette 9 having a thermal transfer ribbon 7 and a ribbon take-up reel hole 8 turns on the mechanical switch 6.
This is done by reading the change in the electric signal when the N / OFF is performed.

Further, at the time of heat-sensitive transfer printing, a device for detecting whether or not the heat-sensitive transfer ribbon 7 is in the ribbon end state is required.

To detect the ribbon end of the thermal transfer ribbon 7, a photo interrupter 10 is provided on the carriage 5 shown in FIG.
In addition, in order to make the photo interrupter 10 read the ribbon end state in the thermal transfer ribbon cassette 9, a ribbon end reader 11 is formed by vapor-depositing Al on the printing surface side of the ribbon for an arbitrary length from the end of the thermal transfer ribbon 7. Infrared rays emitted from the light emitting diode of the photo interrupter 10 are not reflected by the printable thermal transfer ribbon 7, but are reflected by the ribbon end reader 11 in the ribbon end state. The infrared rays received by the light receiving element 10 are converted into an electric signal and the change in the electric signal is read. As shown in FIG. 8 (A), the circuit for reading the electric signal from the photo interrupter 10 is in a printable state, the infrared rays emitted from the light emitting diode of the photo interrupter 10 are not reflected by the thermal transfer ribbon 7, voltage V across the R _L the resistance R _L does not flow current in
_L becomes “L”, and as shown in FIG. 8 (B), in the ribbon end state, the infrared rays emitted from the light emitting diode of the photo interrupter 10 are the ribbon end reader 11
Since reflected by the reflected light current I _L flows through the resistor R _L is received by the light receiving element of the photo interrupter 10, the voltage V _L across the resistor R _L operates as to "H".

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention That is, in the conventional device, a device for detecting whether the thermal transfer ribbon cassette 9 is mounted or not mounted and a device for detecting the ribbon end of the thermal transfer ribbon 7 are respectively provided. Each requires two in total, and the installation of each of the above two detection devices has a problem that it is against the market needs of the thermal printer, which requires lower cost, lighter weight, and smaller size. ..

In view of the above problems, the present invention provides a low cost, lightweight, compact thermal printer.

Means for Solving the Problems In order to solve the above problems, a thermal printer according to the present invention is provided on a carriage for detecting whether a thermal transfer ribbon cassette is mounted or not mounted and for detecting a ribbon end of a thermal transfer ribbon. The photointerrupter provided and the infrared ray emitted from the photointerrupter are reflected so that the photointerrupter can read that the thermal transfer ribbon of the thermal transfer ribbon cassette is in the ribbon end state. A thermal transfer ribbon cassette having a ribbon end leader in which a substance that reflects infrared rays is vapor-deposited on the printing surface side of the thermal transfer ribbon for an arbitrary length from the end of the thermal transfer ribbon, and the distance from the photo interrupter to the ribbon end leader surface. Attaching the thermal transfer ribbon to any position different from The configuration is such that a reflector having an arbitrary area that can be hidden by not mounting is provided.

Operation According to the above configuration, the present invention can perform two types of detection functions, that is, the detection of whether the thermal transfer ribbon cassette is mounted or not mounted and the detection of the ribbon end of the thermal transfer ribbon with one detection function.

Example Hereinafter, regarding the thermal printer of one example of the present invention,
A description will be given with reference to the drawings.

First, as shown in FIG. 1, a thermal head 2 for printing by pressing a thermal paper or plain paper 21 against a platen 22 for printing.
3 and a photo interrupter 29 on a carriage 28 having a ribbon take-up spool 27 for winding the thermal transfer ribbon 24 of the thermal transfer ribbon cassette 26 having a thermal transfer ribbon 24 and a thermal transfer ribbon take-up reel hole 25. In order to reflect infrared rays emitted from the photointerrupter 29, the photointerrupter 29 has an arbitrary area at a position a from the front surface of the light receiving and emitting surface and is movable vertically up and down with respect to the upper surface of the carriage 28. A reflecting plate 30 having Al vapor-deposited thereon is provided on the surface of the photo interrupter 29 facing the light emitting / receiving surface.

This reflection plate 30 is used for the photo interrupter 2 when the thermal transfer ribbon cassette 26 is not mounted on the carriage 28.
When the ribbon cassette 26 is mounted on the carriage 28, the ribbon cassette 26 is set to be pushed downward by the ribbon cassette 26.

In addition, the thermal transfer ribbon 2 of the thermal transfer ribbon cassette 26
4, the ribbon end state is the photo interrupter 2
A ribbon end reader 31 is formed by vapor-depositing Al on the printing surface side of the heat-sensitive transfer ribbon 24 for an arbitrary length from the end of the heat-sensitive transfer ribbon 24 so that the data can be read by the reader 9. The relationship between the distance a from the photo interrupter 29 to the reflecting plate 30 and the distance b from the photo interrupter 29 to the ribbon endon leader 31 of the thermal transfer ribbon is set so that a> b, for example, as shown in FIG. ing. In the above setting, when the ribbon end of the thermal transfer ribbon 24 is detected, the infrared ray emitted from the light emitting diode of the photo interrupter 29 in FIG. 3 is the ribbon end reader 3 of the thermal transfer ribbon 24 set at the position of the distance b.
1 is reflected by the photo interrupter 29, is received by the light receiving element of the photo interrupter 29, and the current I _Lb flows through the resistor R _L, and the voltage V _L
b occurs Next, when the thermal transfer ribbon cassette 26 is not mounted, the infrared rays emitted from the photo interrupter 29 of FIG. 3 are moved to the position of the distance a by raising the reflection plate 30 of FIG. The light is reflected by the set reflection plate 30, is received by the light receiving element of the photo interrupter 29, and the current I _L a flows through the resistor R _L , so that the voltage V _L a is generated.

The voltage V _Lb generated when the ribbon end is detected is simultaneously input to both the comparators X and Y in FIG. 3 and compared with the reference voltages Vx and Yy of the respective comparators.
Similarly, the voltage V _La generated when the thermal transfer ribbon cassette is not attached is also input to the comparators X and Y at the same time and compared with the reference voltages Vx and Vy.

At this time, for example, the resistors R ₁ , R ₂ and R of FIG. 3 are set so that the relationship between the reference voltages Vx and Vy of the comparators X and Y of FIG. 3 becomes the voltage level shown in FIG. 4, that is, Vx> Yy. ₃ and R ₄ are selected and set, and the relation between the detection voltages V _L a and V _L b is, for example, the voltage level shown in FIG. 4, that is, V _L b>Vx> V _L a> Vy. If the resistance R _L of FIG. 3 is selected and set as described above, the outputs of the comparators X and Y of FIG. The amount of printable ribbon of the thermal transfer ribbon 24 (ie,
The logic of "H" or "L" is determined depending on whether the ribbon end state or not.

With the above configuration, one inspection device can perform two types of detection functions, that is, detection of whether the thermal transfer ribbon cassette 26 is mounted or not mounted and detection of the ribbon end of the thermal transfer ribbon 24.

The reflector plate 30 shown in FIG. 1 has a structure in which the thermal transfer ribbon cassette 26 is mounted and unmounted as shown in FIG. 5 so as to be movable upright, and the reflector plate 3 shown in FIG.
The above-described detection function can be realized also by the structure in which 0 is rotated by the thermal transfer ribbon cassette 26. Furthermore, the logic shown in FIG. 4 is not limited to this embodiment, and the present invention can be realized by other logic.

As described above, according to the present invention, a photointerrupter used for detecting whether the thermal transfer ribbon cassette is mounted or not mounted and for detecting the ribbon end of the thermal transfer ribbon is provided on the same carriage. A material having a reflection plate having an arbitrary area and reflecting infrared rays by an arbitrary length from the end of the heat-sensitive transfer ribbon to the photointerrupter to read the ribbon end detection of the heat-sensitive transfer ribbon. By using a thermal transfer ribbon cassette equipped with a vapor-deposited ribbon end reader, it is possible to detect whether the thermal transfer ribbon cassette is mounted or not mounted and to detect the ribbon end of the thermal transfer ribbon with one detection mechanism. It is possible to provide a low-cost, lightweight, compact thermal printer.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of a thermal printer according to an embodiment of the present invention, and FIG. 2 shows the relationship between the distance a between the reflector and the photo interrupter in FIG. 1 and the distance b between the ribbon end reader and the photo interrupter. FIG. 3 is an enlarged view showing a detection voltage generating circuit of a thermal printer according to an embodiment of the present invention, and FIG. 4 is a circuit diagram of FIG. FIG. 5 is a diagram for explaining the output when possible, FIG. 5 is a schematic perspective view of a thermal printer in one embodiment when the reflecting plate of the present invention can be undulated, and FIG. 6 shows the reflecting plate of the present invention which can be rotated. FIG. 7 is a schematic perspective view of a thermal printer according to an embodiment of the present invention, FIG. 7 is a schematic perspective view of a conventional thermal printer, and FIGS. 8A and 8B are detection voltage generation circuit diagrams of the conventional thermal printer. 21 ... Thermal paper or plain paper, 22 ... Platen, 2
3 ... Thermal head, 24 ... Thermal transfer ribbon, 26
...... Thermal transfer ribbon cassette with ribbon end reader, 28 ...... Carriage, 29 ...... Photo interrupter, 30 ...... Reflector, 31 ...... Ribbon end reader.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-60-190381 (JP, A) JP-A-60-154094 (JP, A) JP-A-59-227655 (JP, A) JP-A-59- 218885 (JP, A) Actual development Sho 59-97063 (JP, U)

Claims (1)

[Claims] 1. A photo interrupter provided on a carriage for detecting whether a thermal transfer ribbon cassette is mounted or not mounted and for detecting a ribbon end of the thermal transfer ribbon, and infrared rays emitted from the photo interrupter are reflected, In order to cause the photo interrupter to read that the thermal transfer ribbon of the thermal transfer ribbon cassette is in the ribbon end state, the printing surface of the thermal transfer ribbon of any length from the end of the thermal transfer ribbon of the thermal transfer ribbon cassette. A thermal transfer ribbon cassette having a ribbon end leader on which a substance reflecting infrared rays is deposited, and on the same carriage as the photo interrupter, at an arbitrary position different from the distance from the photo interrupter to the ribbon end leader surface, Whether the thermal transfer ribbon cassette is attached or not attached Thermal printer provided with a reflector having a single arbitrary area that may be selectively concealed Te.