JPH0493265A - Thermal printer - Google Patents

Abstract

PURPOSE:To prevent the deterioration of a printing quality by a method wherein a thermal printing energy to be supplied to heating elements of a thermal head is controlled in accordance with the type of a printing fount. CONSTITUTION:A printing energy table is sorted into three tables 1-3. When a CGROM 21 is used, an optimun printing energy table is the table 1, and a CPU 20 heats recording elements of a thermal head 15 based on the printing energy table 1. When a CGROM 22A is used, an optimun printing energy table is the table 2, and the CPU 20 heats the recording elements of the thermal head 15 based on the printing energy table 2. When a CGROM 22B is used, an optimun printing energy table is the table 3, and the CPU 20 heats the recording elements of the thermal head 15 based on the printing energy table 3.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a thermal printer capable of adjusting heating printing energy supplied to a recording element of a thermal head.

(Prior Art) Conventionally, a thermal head is provided which faces a platen that holds a recording medium and has a plurality of recording elements arrayed in a direction perpendicular to the recording direction, and further includes a thermal head that faces a platen that holds a recording medium, and further includes a thermal head that is arranged in a direction orthogonal to the recording direction. head driving means for applying a heating current to;
A thermal printer equipped with a pulse motor for relatively moving the recording medium or the thermal head is configured such that even when the type of printing font or the type of transfer ribbon changes, the supply to the recording element of the thermal head remains unchanged. There was no control to change the printing energy used for heating.

(Problem to be Solved by the Invention) In the case of the above-mentioned conventional thermal printer, even if the type of printing font or the type of transfer ribbon changes, the printing energy supplied to the recording element of the thermal head is controlled to be changed. For example, if the printing font is a thick line, the recording element of the thermal head will accumulate heat due to the large number of dots, and the ink on the transfer ribbon will easily melt, resulting in what is called a smudged print. The problem was that it was easy.

On the other hand, if the printing font has thin lines, the amount of heat stored in the recording element of the thermal head is small due to the small number of dots (therefore, if the same transfer ribbon as above is used, thick line printing Compared to the case of fonts, the ink on the transfer ribbon is difficult to dissolve, and there is a problem in that so-called blurred printing is more likely to occur.

Therefore, in the present invention, printing can be performed by controlling the heating printing energy supplied to the recording element of the thermal head according to the type of printing font, without using complicated control using complicated electronic circuits or software. The technical problem to be solved is to prevent a decline in quality.

(Means for Solving the Problems) The technical means for solving the above problems includes a platen that holds a recording medium, and a plurality of recording elements facing the platen and arranged in a direction perpendicular to the recording direction. a thermal head, a head driving means for applying heating current to the recording element based on given data, and a pulse motor for relatively moving the recording object or the thermal head. The thermal printer recognizes the type of printing font printed on the recording medium, and outputs a control signal for causing the head driving means to supply printing energy corresponding to the printing font to the recording element of the thermal head. The purpose of the present invention is to provide a configuration that includes a print control means for controlling the print quality.

(Operation) According to the thermal printer configured as described above, the printing control means provided in the thermal printer recognizes the type of printing font printed on the recording medium, and then applies printing energy corresponding to the printing font to the head of the recording medium. Since the driving means outputs a control signal to be supplied to the recording element of the thermal head, it is possible to print without deteriorating print quality even when the types of printing fonts are different.

(Example) Hereinafter, a first example of the present invention will be described with reference to the drawings.

In this embodiment, the present invention is applied to an electronic tape writer equipped with a thermal printer.

As shown in FIG. 1, there is a keyboard 4 on the top surface of the tape writer body 1, on which a power switch 2, a print button 3, etc. are arranged, and a dial 5 for inputting characters, symbols, etc. is arranged on the right side of the keyboard 4. ing. A liquid crystal display (LCD) 6 is provided above it for displaying input characters and symbols. Characters and symbol strings input using the dial 5 are printed on a tape, which is a recording medium, by a thermal head, which will be described later, using a thermal transfer ribbon built into the tape writer main body 1.

FIG. 2 is a perspective external view of the drive section of the electronic tape writer.

A pulse motor 11, a roller holder 12, a head portion 13, etc. are mounted on the motor holder IO. The power of the pulse motor 11 is transmitted to the tape feed roller 14 via a gear, and the tape and thermal transfer ribbon (not shown), which are recorded objects, are moved relative to the thermal head 15.

Furthermore, the platen roller 17 and the thermal head 15 are
A roller release lever 16 pinches the tape and a thermal transfer ribbon (not shown), presses them, and releases them.

FIG. 3 is a control block diagram of the electronic tape writer.

Based on the print data input from the keyboard 4 and dial 5, the CPU 20 reads a character generator ROM (CGROM) provided inside the tape writer main body l.
) 21 or externally installed character generator ROM 22A, 22B, and displays the dot pattern data on the liquid crystal display 6,
and is configured to output to the thermal control circuit I8. The CGROM 21 has built-in print data of a standard font, and the CGROM 22A has built-in print data of, for example, Loli, whose font itself is composed of thick lines.
The CGROM 22B contains print data of, for example, a script in which the font itself is composed of thin lines.

Further, the CPU 20 outputs a drive signal to the motor drive circuit 19 according to the operation of the print button 3, and outputs a drive signal to the pulse motor 11.
drive.

Furthermore, the CPU 20 includes the character generator R.
OM (CGROM) 21 or externally installed character generator ROMs 22A and 22B are identified and detected, and each character generator R is
A character generator ROM detection circuit (CGROM detection circuit) 23 that outputs an identification signal corresponding to the OM is connected.

In the above configuration, when the print button 3 is operated, the motor drive circuit 19 outputs a pulsed drive voltage to the pulse motor 11.
is driven, and the tape and ribbon are connected to the thermal head 1.
5, and the thermal control circuit 18
The thermal head 15 is driven, and the characters or symbols input using the dial 5 are transferred onto the tape.

Note that the CPU 20 has the power switch (ON10FF).
key) 2, when the power switch 2 is turned on, the CP
A reset circuit 32 that initializes U20, an oscillation circuit 33 that oscillates a reference clock, and a voltage detection circuit 34 that detects the voltage of the built-in battery are connected. Further, a column driver 6A and a common driver 6B for driving the liquid crystal display 6 are connected to the CPU 20.

The internal ROM of the CPU 20 includes the character generator ROM (CGROM) 2l, or character generator ROMs 22A and 22 installed externally.
There is a built-in printing energy table that classifies the printing energy supplied to each recording element of the thermal head 15 when heating the recording element of the thermal head 15 corresponding to each B, and FIG. 4 shows the printing energy table. is shown on the front page.

As shown in Figure 4, the printing energy key table is from ■ to ■.
CGROM21
When the printer is using the optimum printing energy table (2), the CPU 20 heats the recording element of the thermal head 15 based on the printing energy key table (2). Also, when CGROM22A is used, its optimum printing energy key table is
The recording element of the thermal head 15 is heated based on the printing energy table (■), and when the CGROM 22B is used, the optimum printing energy table (■) is used, and the CPU 20 heats the recording element of the thermal head 15 based on the printing energy table (■). heating the recording element. In other words, C with built-in print data whose font consists of thick lines.
When GROM22A is used, a lower printing energy table ■ is selected to avoid so-called print collapse, while when CGROM22B with built-in print data consisting of fonts or thin lines is used,
In order to avoid so-called blurred printing, a high printing energy table is selected.

Incidentally, each of the printing energy tables ■■■ may be built in the corresponding character generator ROM 21.22A22B.

Next, a second example will be described.

The second embodiment adjusts and controls the printing energy supplied to the recording element of the thermal head 15 of an electronic tape writer similar to the first embodiment, depending on the combination of the font type and the transfer cassette containing the transfer ribbon. It is. Second
The configuration of the electronic tape writer of the embodiment is as shown in FIGS. 1 and 2, and the control configuration is shown in FIG. 5. As shown in FIG. 5, in addition to the CGROM detection circuit 23 shown in FIG. It is connected. A transfer ribbon is attached to the transfer cassette, and a plurality of types of transfer cassettes are prepared depending on the type of the attached transfer ribbon.

FIG. 6 shows a state in which the transfer cassette 41 is set on the lower surface of the tape writer main body 1. The transfer cassette setting section of the tape writer main body 1 is equipped with cassette detection switches 42 and 43 that identify the type of the set transfer cassette 4I and output a signal according to the type. This cassette detection switch 42.43
constitutes the above-mentioned transfer cassette detection circuit 24, and the transfer cassette is detected by detection means as shown in FIG. 7(A), FIG. 7(B), FIG. 7(C), and FIG. 7(D). Cassette 41
It identifies the type of

FIG. 7(A) shows a state in which the transfer cassette 41 is not set, and in this case, both the cassette detection switches 42 and 43 are in the off state.

FIG. 7(B) shows a state in which it is detected that the transfer cassette 41A is set when the transfer cassette 41A to which the most frequently used ribbon is attached among the transfer cassettes 41 is set. It is. Transfer cassette 4
1A has a hole into which the actuating piece of the cassette detection switch 43 enters, and when the transfer cassette 41A is set, the cassette detection switch 42 is turned on and the cassette detection switch 43 is turned off, so the CPU 20 detects the cassette. It can be detected that the transfer cassette 41A is set based on the output signal state of the switches 42 and 43.

Of the transfer cassettes 1-41, FIG. 7(C) shows a transfer cassette 41 with a built-in ribbon that uses ink with a component that easily melts.
This figure shows a state in which when transfer cassette 41B is set, it is detected that transfer cassette 41B is also set. The transfer cassette 41B has a hole into which the operating piece of the cassette detection switch 42 enters, and when the transfer cassette 41B is set, the cassette detection switch 42 is turned off and the cassette detection switch 43 is turned on, so that the CPU
20 can detect that the transfer cassette 41B is set based on the pressure signal state of the cassette detection switches 42 and 43.

Of the transfer cassettes 41, FIG. 7(D) shows a transfer cassette 41C with a built-in ribbon that uses ink with a component that is difficult to melt.
This figure shows a state in which it is detected that the transfer cassette 41C is also set when the transfer cassette 41C is set. Since the transfer cassette 41C does not have a hole into which the operating pieces of the cassette detection switches 42 and 43 fit, when the transfer cassette 41C is set, the cassette detection switches 42 and 4
3 are both turned on, the CPU 20 can detect that the transfer cassette 41C is set.

FIG. 8 shows the optimum printing energy tables A, B, C, and D when the CGROMs 21, 22A, 22B and the transfer cassettes 41A, 41B, 41C are used in combination.
, E, F, G, H, and I. Incidentally, the energy tables A to I mentioned above also have the CPU 2
It is built into the internal ROM of 0.

In FIG. 8, the transfer cassette 41A is the most frequently used one as described above, and the transfer cassette 41A and C
GROM2], printing is performed using standard printing control, so the optimum printing energy is set as printing energy table A.

Furthermore, since the transfer cassette 41B uses ink that easily melts in its ribbon, when using the CGROM 21, it is recommended to use the printing energy table B, which has a lower printing energy, in order to avoid so-called printed characters being crushed. It is set.

Furthermore, since the transfer cassette 41C uses ink that is difficult to melt for its ribbon, in order to avoid so-called blurred printing, when using the CGROM 21, it is recommended to use the printing energy table C with a higher printing energy. It is set.

Similarly to the above, when using the CGROM22A, the optimum printing energy tables D, E, and F of the respective transfer cassettes 41A, 41B, and 41C are selected, and the CGROM2
When using 2B, each transfer cassette 41A
, 41B, 41C optimal printing energy table G, H
, I are selected.

As described above, from the printing energy table A that is optimal according to the type of font and the type of transfer cassette, ■
or selected.

Next, a third embodiment of the present invention will be described.

In the third embodiment, since the resistance value of the recording element varies with respect to the standard value in the process of manufacturing the thermal head 15, the resistance value range of the manufactured thermal head 15 is ranked, for example, from the highest resistance value. X (220-200Ω),
Rank Y (240~220Ω), and Rank Z (260
~240Ω), and a printing energy table based on the respective head ranks X, Y, and Z.
Printing is controlled using a printing energy table that is made common to the printing energy table based on the use of the CGROMs 21, 22A, 22B and the transfer cassettes 41A, 41B, 41C of the second embodiment.

The configuration of the electronic tape writer of the third embodiment is similar to the configuration of the second embodiment shown in FIGS. 1, 2, and 5.

FIG. 9 shows CG similar to the first and second embodiments.
ROM21.22A, 22B and various transfer cassettes (A)
, (a), and (t), as well as the printing energy table selected at that time. Note that this printing energy table is also the same as the first one. Similar to the second embodiment, it is built in the internal ROM of the CPU 20.

In Fig. 9, the transfer cassette (A) is the most frequently used one, and this transfer cassette (A) and the CGROM21
When using , it is printed using standard printing control, so
The optimum printing energy is shown in printing energy table C. In addition, since the transfer cassette (A) uses ink that easily melts in its ribbon, when using CGROM21, it is recommended to use printing energy table b, which has a lower printing energy, in order to avoid so-called crushed print. is set to .

Furthermore, since the transfer cassette (2) uses ink that is difficult to melt for its ribbon, when using CGROM21, it is recommended to use a printing energy table d with a higher printing energy to avoid so-called blurred printing. is set to .

Also, if the transfer cassette (A) is selected, the CG
When using ROM21, print energy table C is selected, and when using CGROM22A, since the font itself is composed of thick lines, the print energy is set to a lower print energy to avoid so-called excessive printing. Table b is selected. Furthermore, C
When using GROM 22 B, since the font itself is composed of thin lines, the printing energy table d, which is set to a higher printing energy, is selected in order to avoid so-called printing force streaks.

Figure 10 shows the differences between the CGROMs 21, 22A, 22B, various transfer cassettes (A), (B), and (T) and the head ranks X, Y, and Z, which are printed so that they are equivalent in terms of printing energy. energy table a, b, c, d
, e, f, and g.

Moreover, FIGS. 11(A), (B), and (C) show the CGROM 21.
22A, 22B and the various transfer cassettes (A) and (B)
, (1) and the above-mentioned printing energy tables a, b, c, and d.

This shows the assignment of e, f, and g.

In this way, printing energy table a, b, cd +
e + f 1g to CGROM21.22A, 22B
By setting the differences between the various transfer cassettes (A), (B), and (T) and the head ranks X, Y, and Z to be equivalent in terms of printing energy, a small number of printing energy tables can be created. Appropriate printing control can be performed with

In addition, CGROM21.22A, 22B, various transfer cassettes (A), (B), (T) and the head ranks x, y,
If the differences with z are not set to be equivalent in terms of printing energy, even if the head ranks are divided into three ranks, X, Y, and Z, which are relatively small, as shown in Fig. 12 (
As shown in A), (B) and (C), a, b, c, d, e,
f.

g+h+l! Jl k+ L m+
n+ Or p+ Qvr, s, t,
27 types of printing energy tables must be set: u, V, w, x, w, z, zz.

Therefore, if the above-mentioned differences are set to be equivalent in terms of printing energy, appropriate printing control can be performed with a small number of printing energy tables.

(Effects of the Invention) As described above, according to the present invention, there is provided a thermal head including a platen that holds a recording medium, and a plurality of recording elements arranged in a row in a direction perpendicular to the recording direction, facing the platen. A thermal printer comprising a head driving means for applying a heating current to the recording element based on given data, and a pulse motor for relatively moving the recording medium or the thermal head. The structure is configured to control the printing energy supplied to the recording element of the thermal head according to the type of printing font without using complicated control using electronic circuits or software. This has the effect that printing quality can be improved.

[Brief explanation of the drawing]

The drawings relate to embodiments, and FIG. 1 is a perspective external view of an electronic tape writer, FIG. 2 is a perspective external view of a drive unit of the electronic tape writer, FIG. 3 is a control block diagram of the first embodiment, and FIG. 4 1 is a table diagram showing a printing energy key table corresponding to the printing font of the first embodiment. Also, FIG. 5 is a control block diagram of the second embodiment and the third embodiment, FIG. 6 is a perspective view for explaining installation of the transfer cassette, and FIGS. 7 (A), (B), and (C). , (D) is an explanatory diagram of the operation of the detection switch for detecting the type of transfer cassette,
FIG. 8 is a chart of a printing energy table for combinations of printing fonts and transfer cassettes in the second embodiment. Furthermore, FIG. 9 is a table of a printing energy table according to the third embodiment, FIG. 10 is a table of a printing energy table set to be equivalent in terms of printing energy, and FIG. 11 (A).
(B) and (C) are charts of printing energy key tables for each head rank, and FIG. 12 is a chart of a printing energy table when the printing energies are not set to be equivalent. 15: Thermal head 18: Thermal control circuit 20: CPU 21: CGROM (internal) 22A: CGROM (external) 22B: CGROM (external) 23: Character generator ROM detection circuit 24: Transfer cassette detection circuit

Claims (1)

[Scope of Claims] A platen that holds a recording medium, a thermal head that faces the platen and has a plurality of recording elements arrayed in a direction perpendicular to the recording direction, A printing font printed on the recording medium in a thermal printer comprising a head driving means for applying a heating current to an element and a pulse motor for relatively moving the recording medium or the thermal head. A thermal printer comprising a printing control means that recognizes the type of the printing font and outputs a control signal for causing the head driving means to supply printing energy corresponding to the printing font to the recording element of the thermal head. .