JPH05193174A - Line thermal head and ink ribbon - Google Patents

Abstract

PURPOSE:To prevent the generation of the running of a printed character or the wrinkles of an ink ribbon by providing a transmission type sensor transmitting light through the ink uncoated part of the ink ribbon to detect the thickness of the base of the ink ribbon and altering the pulse width of a strobe signal corresponding to the thickness of the base. CONSTITUTION:A transmission type sensor 28 is arranged in opposed relation to the ink uncoated part provided to the edge part of an ink ribbon. The digital level data from the transmission type sensor is sent to a control part 21 through an I/O port 23 to judge the base thickness of the ink ribbon. The base thickness is divided into levels over several stages and the pulse widths of the preset strobe signals corresponding to the levels are stored in an ROM. Each of the pulse widths of the strobe signals is selected from a table on the basis of the judged base thickness and, when the base thickness is large, the pulse width of the strobe signal is widened to perform printing extending the current supply time of a heating resistor element and, when the base thickness is small, the pulse width of the strobe signal is narrowed to perform printing shortening the current supply time of the heating resistor element.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line thermal printer and an ink ribbon.

[0002]

2. Description of the Related Art Conventionally, in a line thermal printer, a thermal head constructed by arranging a large number of heating resistance elements in a line is opposed to a roll paper on a platen via an ink ribbon, and the above heating resistance elements are arranged. Printing is performed by selectively driving.

FIG. 2 is a schematic view showing a cross section of a conventional line thermal printer. In the figure, 1 is a line-type thermal head configured by arranging a large number of heating resistance elements in a line, 2 is a platen disposed so as to face the thermal head 1, and 3 is between the thermal head 1 and the platen 2. The roll paper fed to the paper is an ink ribbon.

The platen 2 is rotated by a motor (not shown) to feed the roll paper 3. At this time, the ink ribbon 4 is also fed at the same time, and the heating resistance element of the thermal head 1 is selectively heated while the roll paper 3 and the ink ribbon 4 are sandwiched, so that the roll paper 3 has characters, figures and the like having a dot configuration. Is printed. FIG. 3 is a circuit block diagram for operating a conventional line thermal printer.

In the figure, 21 is a microprocessor,
A control unit including a read only memory (ROM), a random access memory (RAM), a timer, etc., 22 is an interface line for inputting print data from an external device, 23 is a thermal head 1, a motor 24, etc. I / O port for connecting the control unit 21 and the common bus 25.

The motor 24 is connected to the I / O port 23.
It is driven by a motor driver circuit 26 connected to. FIG. 4 is a block diagram showing the structure of a conventional thermal head. In the figure, 10 is a shift register circuit (S
R), in synchronization with the clock (CLOCK) signal,
A data (DATA) signal for one line is serially input and stored. Reference numeral 11 denotes a latch circuit (LT), and DATA stored in the shift register circuit 10 by inputting a pulse to the latch (LATCH) signal.
Capture the signal.

Further, r ₁ , r ₂ , ..., R _m are m heating resistance elements, which are divided into n blocks, and m
Make up the dots. Output data of the latch circuit 11 and strobe (STB) signal (STB) for each block
, STB2, ..., STBn) are input to the NAND circuit 12 to obtain a logical product, and as a result, the heating resistor elements r ₁ , r ₂ , ..., R _m are selectively energized to generate heat. Is becoming

Next, the operation of the line thermal printer having the above structure will be described. FIG. 5 is a time chart showing the operation of the conventional line thermal printer. In the figure, when the motor 24 (FIG. 3) is driven, the roll paper 3 (FIG. 2) is sent from the i−1 line to the i line, and when the printing of the i line is started, the DA paper is synchronized with the CLOCK signal.
The TA signal is input to the shift register circuit 10 (FIG. 4) and transferred.

The shift register circuit 10 has D for one line.
When the ATA signal is stored, a short pulse is input to the LATCH signal, and the DATA signal stored in the shift register circuit 10 is fetched by the latch circuit 11.
Next, the STB signal having a constant pulse width is sequentially sent in time division for each block, and the output of the NAND circuit 12 corresponding to the STB signal is set to the low level to generate the heating resistance elements r ₁ , r ₂ , ..., R _m.
Is exothermic. In this case, only the latch circuit 11 outputting a high level signal generates heat.

By the above operation, the printing operation for one line is completed, and thereafter, the same operation is continuously performed for the characters,
Graphics etc. are printed.

[0011]

However, in the above-mentioned conventional line thermal printer, since the thickness of the base material of the ink ribbon 4 used and the thickness of the ink are different, the ink transferred onto the roll paper 3 is different. Of the energy applied to the thermal head 1 and the combination of the energy applied to the thermal head 1 and the ink ribbon 4.
If the combination of the pressing force applied by the thermal head 1 and the pressing force applied by the thermal head 1 is not appropriate, the printing quality will be significantly reduced.

The present invention can solve the problems of the conventional line thermal printer described above and prevent the print quality from deteriorating due to the difference in the thickness of the base material of the ink ribbon used and the thickness of the ink. An object is to provide a line thermal printer and an ink ribbon.

[0013]

Therefore, in a line thermal printer and an ink ribbon of the present invention, a shift register circuit to which a data signal is input, a latch circuit for latching the data signal of the shift register circuit, and the latch. Ink ribbon formed by applying ink to the surface of a light-transmitting and colored base material by a line-type thermal head consisting of a large number of heating resistance elements that selectively generate heat in response to circuit output data and strobe signals. It is designed to print using.

The ink ribbon is provided with a portion not coated with ink, and light is transmitted to that portion.
A transmissive sensor for detecting the base thickness is provided. The memory of the line thermal printer stores the base thickness of the ink ribbon and the pulse width data of the strobe signal set in advance corresponding to the base thickness, and when the base thickness is detected, it corresponds to the base thickness. The pulse width data is read from the memory and output to the thermal head.

In the second embodiment, an ink ribbon constituted by applying a light-transmitting ink to the surface of a light-transmitting base material is used, and the transmission type sensor is coated with the ink of the ink ribbon. The ink is detected by allowing light to pass through the exposed portion. The memory stores the ink thickness and the pulse width data of the strobe signal preset corresponding to the ink thickness, and the pulse width data corresponding to the detected ink thickness is read from the memory. It outputs to the thermal head.
Further, in the third embodiment, a pressing force adjusting means for pressing the thermal head against the platen with the set pressing force is provided, and the thermal head is used to
Printing is performed using an ink ribbon formed by applying ink to the surface of a light-transmitting and colored base material.

The ink ribbon is formed with a portion not coated with ink, and light is transmitted through the portion.
A transmissive sensor for detecting the base thickness is provided. The memory of the line thermal printer stores the base thickness of the ink ribbon and the preset pressing force data corresponding to the base thickness. When the base thickness is detected, the pressing force data corresponding to the base thickness is detected. The data is read from the memory and output to the thermal head.

In the fourth embodiment, a pressing force adjusting means for pressing the thermal head against the platen with a set pressing force is provided, and the thermal head causes the surface of the light-transmissive base material to move. Printing is performed using an ink ribbon configured by applying a light-transmitting ink. The ink ribbon is provided with a transmissive sensor that transmits light to the ink-coated portion and detects the ink thickness. The memory stores ink thickness and pressure data preset corresponding to the ink thickness, and the pressure data corresponding to the detected ink thickness is read from the memory to read the thermal head. It is designed to output to.

[0018]

According to the present invention, a shift register circuit to which a data signal is input as described above, a latch circuit for latching the data signal of the shift register circuit, and output data of the latch circuit and a strobe signal are selected. With a line-type thermal head consisting of a number of heat-generating resistance elements that generate heat, printing is performed using an ink ribbon configured by applying ink to the surface of a light-transmitting and colored base material. There is. Therefore, the heating resistance element corresponding to the data signal generates heat to heat the ink ribbon, and printing is performed by thermal transfer.

A portion not coated with ink is formed on the ink ribbon, and a transmissive sensor for transmitting light to detect the base thickness is provided in the portion. When the transmissive sensor detects the base thickness, the pulse width of the strobe signal is changed according to the base thickness, and the heating resistor element generates heat by the strobe signal.

Therefore, the memory of the line thermal printer stores the base thickness of the ink ribbon and the pulse width data of the strobe signal preset corresponding to the base thickness, and when the base thickness is detected, the data is stored. Data of the pulse width corresponding to the base thickness is read from the memory. In the second embodiment, an ink ribbon configured by applying a light-transmissive ink on the surface of a light-transmissive base material is used, and the transmissive sensor is provided on the ink-coated portion of the ink ribbon. Transmit light,
Detect ink thickness.

When the ink thickness is detected, the pulse width data of the strobe signal corresponding to the ink thickness is read from the memory and output to the thermal head.
Further, in the third embodiment, the pressing force adjusting means for pressing the thermal head against the platen with the set pressing force is provided, and the surface of the light-transmitting and colored base material is provided by the thermal head. Printing is performed by using an ink ribbon configured by applying ink to.

The transmissive sensor transmits light to a portion not coated with ink to detect the base thickness. And
When the base thickness is detected, the pressing force data corresponding to the base thickness is read from the memory and output to the thermal head. In the fourth embodiment, a pressing force adjusting means for pressing the thermal head against the platen with a set pressing force is provided, and the thermal head causes the surface of the light-transmissive base material to transmit light. Printing is performed using an ink ribbon configured by applying the above ink.

The transmissive sensor transmits light to a portion coated with ink to detect the ink thickness. Then, when the ink thickness is detected, the data of the pressing force corresponding to the ink thickness is read from the memory and output to the thermal head.

[0024]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 6 is a schematic view showing a cross section of the line thermal printer of the present invention. In the figure, 1 is a line-type thermal head configured by arranging a large number of heating resistance elements in a line, 2 is a platen disposed so as to face the thermal head 1, and 3 is between the thermal head 1 and the platen 2. The roll papers 4 and 4 are ink ribbons formed by applying ink to the surface of the base material.

The platen 2 is rotated by a motor (not shown) to feed the roll paper 3. At this time, the ink ribbon 4 is also fed at the same time, and the heating resistance element of the thermal head 1 is selectively heated while the roll paper 3 and the ink ribbon 4 are sandwiched, so that the roll paper 3 has characters, figures and the like having a dot configuration. Is printed. 28 is the ink ribbon 4
Is a transmissive sensor arranged to detect the thickness of the base material, that is, the base thickness.

Next, the control device of the line thermal printer having the above-mentioned structure will be described. FIG. 1 is a block diagram of a line thermal printer showing an embodiment of the present invention. In the figure, 21 is a microprocessor, ROM, RAM,
A control unit including a timer, 22 is an interface line for inputting print data from an external device, 23 is an I / O port for controlling the thermal head 1, the motor 24, etc. They are connected by the common bus 25.

The motor 24 is connected to the I / O port 23.
It is driven by a motor driver circuit 26 connected to. 28 is a transmissive sensor, and 29 is a sensor level detection circuit for converting the sensor output of the transmissive sensor 28 into digital level data. FIG. 7 is a layout view of a transmission type sensor on a monochrome ink ribbon, FIG. 8 is a layout view of a transmission type sensor on a color ink ribbon, and FIG.
FIG. 9 is a sectional view taken along line AA of FIG. 8.

7 to 9, 4 is an ink ribbon,
Reference numeral 31 is a base portion of the ink ribbon 4, and 32 is an ink application portion on which ink is applied. In the case of the color ink ribbon 4, yellow (Y), magenta (M), cyan (C), and black (Bk) inks are partitioned and applied to the ink application portion 32. Reference numeral 28 denotes a transmissive sensor for detecting the base thickness of the ink ribbon 4, which is arranged so as to face the edge of the ink ribbon 4 which is not coated with ink. The base portion 31 is capable of transmitting the light of the transmissive sensor 28, and
It is colored so that it does not completely block the light. Moreover, a color is selected so that the amount of transmitted light changes according to the base thickness.

FIG. 10 is a characteristic diagram of the base portion of the ink ribbon used in the embodiment of the present invention. As shown in the figure, the base portion 31 of the ink ribbon 4 (FIG. 7) has such a characteristic that when the base thickness increases, the amount of transmitted light decreases and the sensor output of the transmissive sensor 28 decreases. ing. In this case, if the relationship between the base thickness and the sensor output is linear, it is easy to set the STB signal, but it is not necessarily required to be linear. The base thickness is detected at any time in the case of the monochrome ink ribbon 4 and before the winding of the ink ribbon 4 when the power of the line thermal printer is turned on in the case of the color ink ribbon 4.

Next, the operation of the transmissive sensor 28 will be described. FIG. 11 is a detailed view of the transmissive sensor. In the figure, 4 is an ink ribbon, 28 is a transmissive sensor, 2
Reference numeral 9 is a sensor level detection circuit, 34 is a photodiode which emits light when a current flows, 35 is a phototransistor which conducts when it receives light from the photodiode 34, and 36 and 37 are resistors. As shown in FIG. 9, the base portion 31 of the ink ribbon 4 exists between the photodiode 34 and the phototransistor 35. When the photodiode 34 emits light, the light transmitted through the base portion 31 causes the phototransistor 35 to pass through. Irradiate.

In this case, as described above, the base portion 31
Since the light corresponding to the base thickness is transmitted, the phototransistor 35 becomes conductive according to the base thickness. A sensor level detection circuit 29 is connected between the phototransistor 35 and the resistor 36, and the sensor level detection circuit 29 detects a voltage between the two and converts it into digital level data.

The above digital level data is sent to the controller 21 via the I / O port 23, and the controller 21 determines the base thickness of the ink ribbon 4. Further, the thermal head 1 is determined by the determined base thickness. Is controlled. Here, the base thickness is divided into several levels, and control is performed according to each level. That is, the pulse width of the STB signal output to the thermal head 1 is changed corresponding to each level.

FIG. 12 is a relationship diagram between the base thickness and the pulse width of the STB signal. As shown in the figure, the larger the base thickness, the wider the pulse width of the STB signal, and the data of this pulse width is stored in the ROM as a table.
As described above, when the base thickness is large, the pulse width of the STB signal is widened to increase the energization time of the heating resistance element, and when the base thickness is small, the pulse width of the STB signal is narrowed. Printing is performed with the heating resistor element energized for a short time.

FIG. 13 is a time chart of the STB signal when the base thickness is large, and FIG. 14 is a time chart of the STB signal when the base thickness is small. As shown in the figure,
When the base thickness is large, the pulse width is wide, and when the base thickness is small, the pulse width is narrow. Therefore, when the base thickness of the ink ribbon 4 is large, a large amount of energy is applied to the ink ribbon 4 so that printing is not blurred, and when the base thickness is small, excess energy is applied to the ink ribbon 4. It is possible to prevent the occurrence of printing drips and wrinkles of the ink ribbon 4 due to excessive heating.

As described above, the pulse width data of the STB signal is stored in the ROM, which is a storage means in the control unit 21.
Is stored in the memory, and is read by the microprocessor as needed and output to the thermal head 1. S
The pulse width of the TB signal can also be used for control of other thermal heads 1, such as temperature control and history control. In any control, the pulse width of the STB signal depends on the base thickness of the ink ribbon 4. It is narrowed and widened.

Next, a second embodiment of the present invention will be described. FIG. 15 is an arrangement state diagram of a transmission type sensor on a monochrome ink ribbon according to the second embodiment of the present invention, and FIG.
FIG. 17 is an arrangement view of a transmission type sensor on a color ink ribbon according to the second embodiment of the present invention, and FIG.
FIG. 15 to 17, 4 is an ink ribbon, 31 is a base portion of the ink ribbon 4, and 32 is an ink application portion on which ink is applied. In the case of the color ink ribbon 4, yellow (Y), magenta (M), cyan (C), and black (Bk) inks are partitioned and applied to the ink application portion 32.

Reference numeral 41 is a transmissive sensor for detecting the ink thickness of the ink ribbon 4, that is, the ink thickness. The transmissive sensor 41 is arranged at a position facing the ink application portion 32. In this case, the base portion 31 is not colored. The ink of the ink ribbon 4 is
A material having a characteristic that the amount of light transmitted through the ink application portion 32 changes according to the ink thickness is used.

FIG. 18 is a characteristic diagram of the ink of the ink ribbon used in the second embodiment of the present invention. As shown in the figure, the ink of the ink ribbon 4 (FIG. 15) has a characteristic that when the ink thickness increases, the amount of light that passes through decreases and the sensor output of the transmissive sensor 41 decreases. .. In this case as well, it is not necessary to be linear.

The ink thickness thus detected is the sensor level detection circuit 29 (FIG. 11) as in the above embodiment.
Sent to and converted to digital level data. Then, the controller 21 determines the ink thickness of the ink ribbon 4 from the digital level data, and the thermal head 1 is controlled according to the determined ink thickness. Also in this case, the ink thickness is divided into several levels, and the pulse width of the STB signal is changed corresponding to each level.

FIG. 19 is a diagram showing the relationship between the ink thickness and the pulse width of the STB signal. As shown in the figure, the larger the ink thickness, the wider the pulse width of the STB signal, and the data of this pulse width is stored in the ROM of the control unit 21 as a table. Therefore, when the ink thickness of the ink ribbon 4 is large, a large amount of energy is applied to the ink ribbon 4, and the printing is not blurred.
On the other hand, when the ink thickness is small, excess energy is not applied to the ink ribbon 4, and it is possible to prevent the occurrence of print drift and wrinkles of the ink ribbon 4.

Next, a third embodiment of the present invention will be described. FIG. 20 is a schematic view showing a cross section of the line thermal printer of the present invention. In the figure, 1 is a line-type thermal head configured by arranging a large number of heating resistance elements in a line, 2 is a platen disposed so as to face the thermal head 1, and 3 is between the thermal head 1 and the platen 2. Roll paper to be fed to the sheet, 4 is an ink ribbon, 43 is a transmissive sensor arranged at the same position as in FIGS. 7 to 9 to detect the base thickness of the ink ribbon 4, and 44 is the thermal head 1. A spring for urging the platen 2 away from the platen 2,
Reference numeral 45 is an eccentric cam for adjusting the pressing force of the thermal head 1 against the platen 2, and 46 is a shaft of the eccentric cam 45.

FIG. 21 is a block diagram of a line thermal printer showing the third embodiment of the present invention. In the figure,
Reference numeral 21 is a control unit including a microprocessor, ROM, RAM, timer and the like, 22 is an interface line for inputting print data from an external device, 23 is an I / O for controlling the thermal head 1, the motor 24 and the like. It is a port and is connected to the control unit 21 by a common bus 25.

The motor 24 is connected to the I / O port 23.
It is driven by a motor driver circuit 26 connected to. Further, 43 is a transmissive sensor arranged to detect the base thickness of the ink ribbon 4, 29 is a sensor level detection circuit for converting the sensor output of the transmissive sensor 43 into digital level data, and 48 is the above-mentioned. A pulse motor for rotating the eccentric cam 45 and a motor driver circuit 49 for driving the pulse motor 48.

In the line thermal printer having the above-described structure, the base portion 31 (FIG. 9) of the ink ribbon 4 is colored to the extent that the light of the transmissive sensor 43 can be transmitted and the light is not completely blocked. Has been done. Also in this case, the base portion 31 has the characteristics shown in FIG.
The amount of light transmitted varies with the base thickness. The detected base thickness is sent to the control unit 21 via the sensor level detection circuit 29, the control unit 21 determines the base thickness of the ink ribbon 4, and the thermal head 1 at the time of printing uses the determined base thickness. The pressing force is set. In this case, the base thickness is divided into several levels, and the pressing force is changed according to each level.

22 is a state diagram of the thermal head in the third embodiment of the present invention, FIG. 23 is a second state diagram of the thermal head in the third embodiment of the present invention, and FIG. 24 is a third state of the present invention. 6 is a third state diagram of the thermal head in the example of FIG. The alternate long and short dash line in FIGS.
The position of the second thermal head 1 is shown. As shown in the figure, the pressing force is set by rotating the eccentric cam 45 to change the position of the thermal head 1 during printing, and the rotation angle θ (θ ₁ > θ ₂ ) of the eccentric cam 45 rotates the shaft 46. Is adjusted by the number of pulses given to the pulse motor 48 (FIG. 21). That is, when the base thickness is large, the rotation angle θ is increased to decrease the pressing force, and when the base thickness is small, the rotation angle θ is decreased to increase the pressing force.

FIG. 25 is a relationship diagram between the base thickness and the pressing force of the thermal head. As shown in the drawing, the pressing force of the thermal head 1 is reduced as the base thickness is increased, and the number of pulses for setting this pressing force is stored in the ROM of the control unit 21 as a table. In this way, when the base thickness of the ink ribbon 4 is large, the pressing force is reduced to prevent the occurrence of print drips and wrinkles of the ink ribbon 4, and when the base thickness is small, the pressing force is increased. To improve the transfer efficiency.

Here, the number of pulses of the pulse motor 48 for setting the rotation angle θ as described above is determined by the control unit 21.
Is stored in the ROM, read out by the microprocessor as required, and output to the pulse motor 48 via the I / O port 23 and the motor driver circuit 49. Next, a fourth embodiment of the present invention will be described.

In this case, similarly to the line thermal printer shown in FIGS. 20 and 21, the pressing force of the thermal head 1 is adjusted by the rotation of the eccentric cam 45, and FIGS.
Similar to the transmissive sensor 41 shown in FIG. 7, the ink thickness is detected. Then, as the ink of the ink ribbon 4, one having the same characteristics as in FIG. 18 is selected, and the ink thickness is detected based on the characteristics. The control unit 21 determines the ink thickness level based on the detected ink thickness and changes the pressing force according to the level.

FIG. 26 is a diagram showing the relationship between the ink thickness and the pressing force of the thermal head. As shown in the figure, the thicker the ink thickness, the smaller the pressing force of the thermal head 1, and the number of pulses for setting this pressing force is stored in the ROM of the control unit 21 as a table. In this way, when the ink thickness of the ink ribbon 4 is large, the pressing force is reduced to prevent the occurrence of printing drool and wrinkles of the ink ribbon 4, and when the ink thickness is small, the pressing force is increased. To improve the transfer efficiency.

The present invention is not limited to the above embodiments, but various modifications can be made based on the spirit of the present invention, and these are not excluded from the scope of the present invention.

[0051]

As described above in detail, according to the present invention, printing is performed using an ink ribbon formed by applying ink to the surface of a light-transmitting and colored base material. A transmissive sensor that transmits light to a portion not coated with ink and detects the base thickness is provided. When the transmissive sensor detects the base thickness, the pulse width of the strobe signal is changed according to the base thickness, and the heating resistor element generates heat by the strobe signal.

Further, in the second embodiment, when the transmissive sensor transmits light to the ink-coated portion of the ink ribbon and detects the ink thickness, the pulse width of the strobe signal corresponds to the ink thickness. Is changed. Further, in the third embodiment, the pressing force adjusting means for pressing the thermal head against the platen with the set pressing force is provided, and the ink is applied to the surface of the light transmissive and colored base material. Is used. And
When the transmissive sensor detects the base thickness, the pressing force is changed according to the base thickness.

In the fourth embodiment, an ink ribbon is provided which is provided with a pressing force adjusting means and which is formed by applying a light-transmitting ink to the surface of a light-transmitting base material by the thermal head. It When the transmissive sensor detects the ink thickness, the pressing force is changed according to the ink thickness. In this way, the base thickness or ink thickness is detected, and the strobe signal or pressing force corresponding to the base thickness is
In addition, since the strobe signal and the pressing force corresponding to the ink thickness are changed, the printing will not fade and excess energy will not be applied to the ink ribbon. The occurrence of creases is prevented, and the printing quality is improved.

[Brief description of drawings]

FIG. 1 is a block diagram of a line thermal printer showing an embodiment of the present invention.

FIG. 2 is a schematic view showing a cross section of a conventional line thermal printer.

FIG. 3 is a circuit block diagram for operating a conventional line thermal printer.

FIG. 4 is a block diagram showing a configuration of a conventional thermal head.

FIG. 5 is a time chart showing the operation of a conventional line thermal printer.

FIG. 6 is a schematic view showing a cross section of the line thermal printer of the present invention.

FIG. 7 is a diagram showing an arrangement state of a transmission type sensor on a monochrome ink ribbon.

FIG. 8 is a diagram showing an arrangement state of a transmission type sensor on a color ink ribbon.

9 is a cross-sectional view taken along the line AA of FIG.

FIG. 10 is a characteristic diagram of a base portion of an ink ribbon used in an example of the present invention.

FIG. 11 is a detailed view of a transmissive sensor.

FIG. 12 is a relationship diagram between the base thickness and the pulse width of the STB signal.

FIG. 13 is a time chart of an STB signal when the base thickness is large.

FIG. 14 is a time chart of an STB signal when the base thickness is small.

FIG. 15 is an arrangement view of a transmission type sensor on a monochrome ink ribbon according to a second embodiment of the present invention.

FIG. 16 is a diagram showing the arrangement of transmissive sensors on a color ink ribbon in the second embodiment of the present invention.

17 is a cross-sectional view taken along the line AA of FIG.

FIG. 18 is a characteristic diagram of ink of the ink ribbon used in the second embodiment of the present invention.

FIG. 19 is a relationship diagram between the ink thickness and the pulse width of the STB signal.

FIG. 20 is a schematic view showing a cross section of the line thermal printer of the present invention.

FIG. 21 is a block diagram of a line thermal printer showing a third embodiment of the present invention.

FIG. 22 is a state diagram of a thermal head according to a third embodiment of the present invention.

FIG. 23 is a second state diagram of the thermal head according to the third embodiment of the present invention.

FIG. 24 is a third state diagram of the thermal head according to the third embodiment of the present invention.

FIG. 25 is a relationship diagram between the base thickness and the pressing force of the thermal head.

FIG. 26 is a diagram showing the relationship between the ink thickness and the pressing force of the thermal head.

[Explanation of symbols]

1 the thermal head 2 platen 4 ink ribbon 10 shift register 11 latch circuit 28,41,43 transmission sensor _{r 1, r 2, ...,} r m heating resistance element

Claims (6)

[Claims] 1. (a) A shift register circuit to which a data signal is input, a latch circuit for latching the data signal of the shift register circuit, and a large number which selectively generate heat by receiving output data of the latch circuit and a strobe signal. A line type thermal head composed of a heating resistance element of (1), (b) an ink ribbon formed by applying ink to the surface of a light-transmitting and colored base material, leaving a part thereof, (c) the ink Light is transmitted to the part of the ribbon where the ink is not applied,
A transmission type sensor for detecting the base thickness, (d) a memory for storing the base thickness and pulse width data of a strobe signal preset corresponding to the base thickness, and (e) corresponding to the detected base thickness. A line thermal printer having means for reading pulse width data from the memory and outputting the data to the thermal head. 2. (a) A shift register circuit to which a data signal is input, a latch circuit that latches the data signal of the shift register circuit, and a large number that selectively generate heat by receiving output data of the latch circuit and a strobe signal. The line-type thermal head including the heating resistance element of (1), (b) the ink ribbon formed by applying the light-transmitting ink to the surface of the light-transmitting base material, and (c) the ink of the ink ribbon. A transmissive sensor that transmits light to the applied portion to detect the ink thickness, and (d) a memory that stores the ink thickness and the pulse width data of the strobe signal preset corresponding to the ink thickness, (E) A liner having means for reading out data of a pulse width corresponding to the detected ink thickness from the memory and outputting it to the thermal head. Thermal printer. 3. (a) A shift register circuit to which a data signal is input, a latch circuit that latches the data signal of the shift register circuit, and a large number that selectively generates heat by receiving output data of the latch circuit and a strobe signal. Of a line type thermal head composed of the heating resistance element of (1), (b) a pressing force adjusting means for pressing the thermal head with a pressing force set against the platen, and (c) a light transmissive and colored base material. An ink ribbon formed by applying ink to the surface; (d) a transmissive sensor that transmits light to a portion of the ink ribbon not applied with ink to detect the base thickness; and (e) a base thickness. A memory for storing preset pressure data corresponding to the base thickness, and (f)
A line thermal printer comprising means for reading data of the pressing force corresponding to the detected base thickness from the memory and outputting the data to the thermal head. 4. (a) A shift register circuit to which a data signal is input, a latch circuit for latching the data signal of the shift register circuit, and a large number which selectively generate heat by receiving output data of the latch circuit and a strobe signal. Line type thermal head composed of the heating resistance element of (1), (b) a pressing force adjusting means for pressing the thermal head with a pressing force set against the platen, and (c) a surface of the light transmissive base material. An ink ribbon formed by applying a light-transmissive ink; (d) a transmissive sensor that transmits light to the ink-coated portion of the ink ribbon to detect the ink thickness; and (e) an ink thickness. And (f) a memory for storing preset pressure data corresponding to the ink thickness,
A line thermal printer comprising means for reading data of pressing force corresponding to the detected ink thickness from the memory and outputting the data to the thermal head. 5. A shift register circuit to which a data signal is input, a latch circuit for latching the data signal of the shift register circuit, and a large number of heating resistors that selectively generate heat by receiving output data of the latch circuit and a strobe signal. An ink ribbon used in a line thermal printer having a line-type thermal head composed of elements, characterized in that the ink is applied to the surface of a light-transmitting and colored base material while leaving a part thereof. 6. A shift register circuit to which a data signal is input, a latch circuit for latching the data signal of the shift register circuit, and a large number of heating resistors that selectively generate heat by receiving output data of the latch circuit and a strobe signal. An ink ribbon used in a line thermal printer having a line-type thermal head composed of elements, wherein a light-transmissive ink is applied to the surface of a light-transmissive base material.