JPH03182386A - Heat transfer type color printer - Google Patents

Abstract

PURPOSE:To enable curing of a desired ink layer to a printing starting position by a method wherein an ink layer of each color is discriminated by means of detecting signals outputted from first and second photodetectors when light from first and second light sources to irradiate each ink layer with light of given wavelengths different from each other passes through each ink layer. CONSTITUTION:Since an ink layer discriminating means 14 outputs a drive signal to a motor 8 and a winding roller 7 is rotated, an ink sheet 6 is delivered from a feed roller 9 for running. Meanwhile, a red color light emitting LED 10a and a green color light emitting LED 10b irradiate the ink layer of the ink sheet 6 with red color and green color light. Thus, when the end part of an yellow layer Y of the ink sheet 6 is moved to the positions of the red color emitting LED 10a and the green color light emitting LED 10a, light having passed through the yellow ink layer Y is respectively collected by phototransistors 11a and 11b and output voltages TA and TB are outputted through current-voltage conversion amplifiers 12a and 12b and amplifiers 13a and 13b. The ink layer discriminating means 14 receives the output voltages to stop the motor 8 once, and the yellow ink layer Y is subjected to curing to obtain a printing starting position.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention is directed to heating an ink sheet, on which a plurality of ink layers are provided in a predetermined color order as a set, with a thermal head to create a desired image. The present invention relates to a thermal transfer color printer applied to a video printer or the like that records (prints) characters, etc. on recording paper.

(b) Prior Art This type of color printer device has a structure in which an attached ink sheet is continuously run between a platen and a thermal head. On the other hand, on the ink sheet, for example,
As shown in FIG. 10, a set of yellow ink layer Y, magenta ink layer M1, and cyan ink layer C are provided in this color order. Therefore, when seven portions of the yellow ink layer of the ink sheet are pressed against the recording paper and the ink sheet is heated by the thermal head, the yellow ink is first printed on the recording paper. Next, the magenta ink layer M portion and the cyan ink layer C portion of the ink sheet are sequentially pressed and heated by a thermal head each time they are pressed, so that magenta ink and cyan ink are superimposed and printed on the recording paper.

By the way, in order to perform the above-mentioned overlapping printing, etc., it is necessary to determine whether each ink layer is placed at the printing position (heading). Therefore, conventionally, Japanese Patent Application Laid-Open No. 63-231976
As shown in (Figure 10).

- A barcode 14 for cueing is provided corresponding to the end of the yellow ink layer Y, which is the tip of the ink layer of the set, and the barcode 14 is detected by an optical sensor to determine the cueing position of the printing position. I was trying to do that.

(c) Problems to be Solved by the Invention However, if the barcode 14 for cueing is provided corresponding to the yellow ink layer -Y as in the past, the width of the ink sheet will be reduced by the amount of the barcode 14 provided. It has to be made larger, and a coloring and coating process for providing the barcode 14 is required. Therefore, the manufacturing cost of the ink sheet increases and the ink sheet becomes expensive.

(d) Means for Solving the Problems The color printer according to the present invention includes an ink sheet on which ink layers of a plurality of colors are provided in a predetermined color order, and a thermal head that heats the ink sheet to print out each of the colors. In a thermal transfer color printer that performs color printing on recording paper through an ink layer, a first light source that irradiates each ink layer with light of a predetermined wavelength; and a first light source that irradiates light of a predetermined wavelength different from the first light source to each of the ink layers. a second light source that emits light; a first light receiving element that outputs a detection signal when light from the first light source passes through each of the ink layers; and a first light receiving element that outputs a detection signal when light from the second light source passes through each of the ink layers. a second light receiving element that outputs a detection signal; and an ink layer discriminating means for discriminating the ink layers of each color based on the detection signal of the second light receiving element.

Further, the first light source and the first light receiving element and the second light source and the second light receiving element are arranged at intervals in a direction perpendicular to the transport direction of the ink sheet.

In contrast, the color printer according to the present invention includes an ink sheet on which ink layers of a plurality of colors are provided in a predetermined color order, and a thermal head that heats the ink sheet and prints the recording paper through the ink layers of each color. In a thermal transfer color printer that performs color printing, a first light source that irradiates each ink layer with light of a predetermined wavelength; a second light source that irradiates each ink layer with light of a predetermined wavelength different from that of the first light source; a light source driving means for alternately driving the first and second light sources; a light receiving element that outputs a detection signal when light from the first and second light sources passes through each of the ink layers; and detection of the light receiving element. The ink layer discriminating means for discriminating the ink layers of each color based on a signal is separated from the ink layer discriminating means.

(E) Effect According to the present invention, the first and second light sources irradiate each ink layer with light of different predetermined wavelengths, and the detection is performed when the light from the first and second light sources passes through each ink layer. The first and second light-receiving elements that output signals are arranged respectively, and the ink layer of each color is determined based on the detection signals of the first and second light-receiving elements, so the ink sheet can be made smaller and the ink sheet can be made smaller. It can be done cheaply.

Further, since the first light source and the first light receiving element and the second light source and the second light receiving element are arranged at intervals in the direction perpendicular to the transport direction of the ink sheet, it is possible to accurately define the printing start position.

Furthermore, according to the present invention, first and second light sources irradiate each ink layer with light having different predetermined wavelengths.

1st. a light source driving means that alternately drives the second light source;
and a light receiving element that outputs a detection signal when the light from the second light source passes through each ink layer, and the ink layer of each color is discriminated based on the detection signal of the light receiving element, so it is easy to attach the light source and the light receiving element. In addition, it is possible to more accurately define the printing start position.

(F) Example A first example of the present invention will be described in detail below with reference to FIGS. 1 to 5.

As shown in FIG. 1, the thermal transfer color printer device according to the present invention is equipped with a platen l.

A clamper 2 for clamping the recording paper 3 is disposed on a part of the outer peripheral surface of the platen l, and when the recording paper 3 arrives at a predetermined position, the clamper 2 clamps the recording paper 3.

A thermal head 5 is disposed above the platen l and is controlled by an energization control section 4 as will be described later. The thermal head 5 is fixed to a mounting base (not shown), and is pressed against the outer circumferential surface of the platen 1 via the ink sheet 6 by the swinging of the mounting base. The used portion of the ink sheet 6 is taken up by a take-up roller 7. The unused roll-shaped ink sheet 6 is rotated by a motor 8 via a deceleration mechanism (not shown), and the supply roller 9 is attached to a supply roller 9. The ink sheet 6 is supplied by driven rotation.

Now, shine a light of a predetermined wavelength near the platen l! 11, a red light emitting LED 10a which is a first light source, and a phototransistor 1 which is a first light receiving element with an ink sheet 6 in between.
1a (or photodiodes) are arranged in pairs. In addition, a green light emitting LED 10b, which is a second light source that irradiates light of a predetermined wavelength at intervals in a direction perpendicular to the transport direction of the ink sheet 6 from the position of the red light emitting LED 10a and the phototransistor lla, and a green light emitting LED 10b are placed on both sides of the ink sheet 6. Phototransistors Ilb, which are second light receiving elements, are arranged in pairs. Here, the reason why the red light emitting LEDIOa and phototransistor lla and the green light emitting LEDI Ob and phototransistor llb are arranged apart from each other is to prevent mutual interference with each other.

Next, the phototransistor lla is the red light emitting LEDIOa.
The red light irradiated onto the ink sheet 6 (as seen from the spectrum distribution diagram in Fig. 4, the peak wavelength is 600 to 75%)
0 nm wavelength) passes through the ink layer of the ink sheet 6 and is received by the phototransistor lla, which outputs a detection signal. Furthermore, phototransistor I
Similarly, in lb, the green light irradiated onto the ink sheet 6 from the green light emitting LED 10b (as seen from the spectrum distribution diagram in FIG. When the light is transmitted through the phototransistor llb and received by the phototransistor llb, a detection signal is output.

Here, each detection signal is a current-voltage conversion amplifier +
2a,? 2b and is converted into voltage and amplified Q13a.
, 13b, each ink layer of the ink sheet 6 is discriminated at an ink layer discrimination T stage 14, which will be described later.

On the other hand, as shown in FIG. 2, the ink sheet 6 is provided with a large number of ink layers, each consisting of a yellow ink layer Y, a magenta ink layer M, and a cyan ink layer C, in this order. Further, the barcode 14 that was conventionally provided is not provided at the end of the ink sheet 6, and therefore the width of the ink sheet 6 is small. Furthermore, ink sheet 6
It is possible to increase the number of ink layers while maintaining the same length in the running direction as the conventional one.

By the way, when the yellow ink layer)', the magenta ink layer M, and the cyan ink layer C transmit white light having the same spectrum, each of them has transmittance spectral characteristics as shown in FIG. 3.

Therefore, red light emission with a predetermined wavelength of 600 to 750 nm,
When the red light of EDloa is transmitted through each ink layer, about 80% of the light passes through the yellow ink layer Y and the magenta ink layer N1, while only about a few% of the light passes through the cyan ink layer C. This is 600-750nrn
This is because the curve of the cyan ink layer C corresponds to a valley in the wavelength band.

Furthermore, a green light emitting LED with a predetermined wavelength of 540 to 590 nm.
When green light of 10b is transmitted through each ink layer, about 80% of the light passes through the yellow ink layer)', while only about a few% of the light passes through the magenta ink layer M and the cyan ink layer C. . This is because in the wavelength band of 540 to 590 nm, the curves of the magenta ink layer Y and the cyan ink layer C fall into a valley.

These transmitted lights are transferred to phototransistors lla and ll.
When light is received at point b, different detection signals (
photocurrent) is output, and the current-voltage conversion amplifier 12a, 1
2b, the voltage is converted into a voltage, amplified by amplifiers 13a and 13b, and supplied to the ink layer discrimination means.

According to experiments and measurements, the voltage at TA and TB in FIG.
Voltages v,,v,', VM, VM' obtained by the light transmitted through the magenta ink layer M1 and the cyan ink layer C, respectively.
, vc, vc' are as shown in Table 1.

Zero a color RILEDI'-y't1660nrafUn car M8 ILED beak ii565nm+! Table 1 As can be seen from Table 1, when red light emitting LEDIOa is used, there is a sensitivity difference of more than 10 times in the output voltages of VC vs. VY, V, and vs.
When using b, VY' vs. VM', Vy' vs. vc
It can be seen that the output voltages ' have a sensitivity difference of more than 10 times, so that they have sufficient detection ability.

Next, the operation of the thermal transfer type printer according to the first embodiment of the present invention will be explained together with the operation of the ink layer discriminating means 14 with reference to FIG.

First, the ink layer discriminating means 14 outputs a drive signal to the motor 8 to rotate the five take-up rollers 7, so that the ink sheet 6 is fed out from the supply roller 9 and runs. On the other hand, the red light emitting LED 10a and the green light emitting LED 10b irradiate red and green light toward the ink layer of the ink sheet 6. Therefore, as shown in FIG.
The end of the yellow ink layer Y is the front red light emitting LED.
10a and green LED 10b,
The light transmitted through the yellow ink layer Y is received by phototransistors lla and llb, and is outputted to output voltages TA and TB through current-voltage conversion amplifiers 1312a and 12b and amplifiers +3a and 13b, respectively, as shown in Table 1. is output. These output voltages T are applied to the ink layer discrimination means 1.
Upon receiving the supply of A and TB, it is determined that rI-(J, rHJ), and thereby it is determined that the end of the yellow ink layer Y has moved to the printing start position.

Here, the ink layer discriminating means 14 has an output type ri;
-C has a comparator etc. that compares A and rB respectively.
The output result of the comparator is "[(" or "
L" is output.

As a result, the motor 8 is temporarily stopped: the yellow ink layer Y is brought to the printing start position, and the thermal head 5 is brought into pressure contact with the platen L. At the same time, the energization control section 4 receives a yellow signal from a memory (not shown), and the thermal head 5
energize the heating element. As a result, the yellow ink layer Y of the ink sheet 6 is heated and yellow ink is printed on the recording paper 3.

Thereafter, the pulse motor (not shown) of the platen 1 and the motor 8 of the take-up roller 7 are rotated to continue the eyeing operation. When the printing operation through the yellow ink layer Y is completed, the thermal head 5 is separated and the magenta ink layer M is
A red light emitting LED 10a and a green light emitting LED whose ends are in the front
Move to the DIOI-+ position.

Therefore, output voltages TA and TB are output as shown in Table 1. Further, in the ink layer discriminating means 14, rHJ is determined by these output voltages TA and TB.

Since it is determined to be "L", it is determined that the end of the magenta ink layer M has moved to the printing start position. As a result, the motor 8 is temporarily stopped, the magenta ink layer Y is brought to the printing start position, the thermal head 5 is brought into pressure contact with the platen 1, and a drive signal is output to the energization control section 4. Therefore, the magenta ink layer Y of the ink sheet 6 is heated and the magenta ink is superimposed and printed on the recording paper 3.

When the magenta ink printing operation is completed, the thermal head 5 is separated and the end of the cyan ink layer C moves to the position of the red light emitting LED 10a and the green light emitting LED 10b in front.

Therefore, output voltages TA and TB are output as shown in Table 1. Furthermore, the ink layer discriminating means 14 outputs "L" due to these output voltages TA and TH.

Since it is determined to be "L", it is determined that the end of the cyan ink layer M has moved to the printing start position. As a result, the motor 8 is temporarily stopped, the cyan ink layer Y is indexed to the printing start position, the thermal head 5 is brought into pressure contact with the platen 1, and a drive signal is output to the energization control section 4. Therefore, the cyan ink layer Y of the ink sheet 6 is heated and the recording paper 3
Cyan ink is printed on @Jyu. As a result, three colors are sequentially superimposed and printed, resulting in a color print.

Since the ink layers are adjacent to each other as described above, each ink layer can be discriminated with high precision and the printing start position can be accurately defined.

FIG. 5 shows a second embodiment which is an application of the first embodiment.

As shown in the figure, the red light-emitting LED I Oa and the phototransistor lla and the green light-emitting LED IOb and the phototransistor llb are arranged on the same side, respectively, and reflectors 20 a and 20 b are placed on the opposite side with the ink sheet 6 in between.
This is a configuration with a

In addition, the red light emitting LED 10a and the phototransistor Ila
Shielding plates 21a and 21b are respectively provided between the green light emitting LED 10b and the phototransistor llb to prevent direct reception of red and green light from the red and green light emitting LEDs 10a and IOb.

As a result, although the output voltage is lower than in Table 1, the height of the device can be reduced because the red light emitting LED 10a, the green light emitting LED 10b and the phototransistors lla and llb can be arranged on the same side.

Next, a third embodiment of the present invention will be described with reference to FIG. 6.7.

This embodiment relates to a thermal transfer color printer in which the ink layers are determined by alternately driving first and second light sources that irradiate each ink layer with light of different predetermined wavelengths.

Incidentally, the same parts as in FIG. 1 are given the same reference numerals, and explanations of the same parts are omitted.

As shown in FIG. 3, near the platen 1 there is a red light emitting LED 10a which is a first light source that emits light of a predetermined wavelength, and a red light emitting LED 10a that emits light of a predetermined wavelength. , ED] from the position of the ink sheet 6 in the direction perpendicular to the transport direction of the ink sheet 6 and irradiates light of a predetermined wavelength.
A green light emitting device LT', D 10 b as a light source is arranged, and each LED loa, 1 is arranged with an ink sheet 6 in between.
A phototransistor 33, which is a light receiving element, is arranged at a position facing the center between 0b.

Next, the operation of the thermal transfer type color printer device of this embodiment will be explained together with the operation of the ink layer discriminating means 37.

First, the ink layer discriminating means 37 outputs the drive signal 3 to the motor 8 to rotate the take-up roller 7, so that the ink sheet 6 is fed out from the supply roller 9 and runs. The one-sided color-emitting LED 10a and the green-emitting LED 10b alternately emit red and green light toward the ink layer of the ink sheet 6 by a light source driving means 30.

The light source driving means 30 is composed of a transistor and the like, and first, a clock pulse signal (for example, 200 Hz) with a duty of 50% is inputted to an input terminal. In response to this clock pulse signal, the transistors 31 and 32 are alternately switched and the red light emitting LED I
Oa and green light emitting LED 10b alternately emit light.

Here, VRI is the light intensity of the red light emitting LED 10a, i
l! This is a variable resistor used for lWi. That is, the T produced by red light and green light when transmitted through a transparent ink sheet.
The voltage at C is the same.

Next, as shown in FIG. 3, when the end of the yellow ink layer Y of the ink sheet 6 moves to the position of the red light emitting LED 10a and the green light emitting LED 10b in front, the light transmitted through the Fuji row ink layer Y is transmitted to the phototransistor 33. The output voltage TC is outputted through the current-voltage conversion amplifier 34 and the amplifier 35, respectively. At this time, if the resistance is set so that the voltage when transmitted through the transparent ink sheet is 5 to 6 cm, the output of the transistor 36 becomes "L" depending on each ink layer as shown in FIG.

A "clock pulse" or "H" output is obtained.

Therefore, the ink layer determining means 37 receives this output signal, and in this case it becomes "L", so it is determined that the yellow ink layer Y
It is determined that the edge of has moved to the printing start position.

As a result, the motor 8 is temporarily stopped, the yellow ink layer Y is brought to the printing start position, and the thermal head 5 is brought into pressure contact with the platen 1. At the same time, the 4-volt controller 4 receives a yellow signal from a memory (not shown), and prints the yellow ink layer Y at the printing start position. head 5
energize the heating element. Therefore, the yellow ink layer Y of the ink sheet 6 is heated and yellow ink is printed on the recording paper 3.

After that, the pulse motor (not shown) of the platen 1 and the motor 8 of the take-up reroller 7 are rotated to perform the printing operation! Continue. When the printing operation through the yellow ink layer Y is completed, the thermal head 5 is separated, and the end of the magenta ink layer M is placed in front of the red light emitting section 2, EDIOa, and the green light emitting section LE.
Move to the position of D l Ob.

Therefore, as shown in FIG. 7, the output signal of the transistor 36 is a "clock pulse with approximately 50% duty", and the end of the magenta ink layer M is moved to the printing start position by the ink layer determining means 37. I judge that. As a result, the motor 8 is temporarily stopped, the magenta ink layer Y is brought to the printing start position, and the thermal head 5 is moved to the platen 1.
At the same time, a drive signal is output to the energization control section 4. Therefore, the magenta ink layer)' of the ink sheet 6 is heated and magenta ink is printed onto the recording paper 3 in a superimposed manner.

When the magenta ink printing operation is completed, the thermal head 5 is separated and the end of the cyan ink layer C moves to the position of the red light emitting LED IOa and the green light emitting LED 10b in front.

1, the output signal of the transistor 36 is "f(" as shown in FIG. 7), and the ink layer determining means 37 determines that the end of the cyan ink layer M has moved to the printing start position. As a result, the motor 8 is stopped by −[l, the cyan ink layer Y is brought to the printing start position, and the thermal head 5 is brought into pressure contact with the platen l.
Outputs a drive signal to. Therefore, the cyan ink layer Y of the ink sheet 6 is heated and the cyan ink is superimposed and printed on the recording paper 3. As a result, the three colors are sequentially printed in an overlapping manner, resulting in a color print.

41 of each ink layer of the ink sheet 6 because the LED loa, 10b can be arranged close to each other as shown in Figure 2.
Even if the ink layers do not coincide with the generatrix direction of the outer circumferential surface of the platen 1 for some reason, each ink layer can be discriminated with high precision and the printing start position can be accurately defined. Additionally, the LED and 7-ototransistor can be easily installed.

FIG. 8 shows a fourth embodiment which is an application of the third embodiment.

As shown in the figure, a red light emitting LED 10a and a green light emitting LED
The D10b and the phototransistor 11 are placed on the same side, and the reflection plate 4 is placed on the opposite side with the ink sheet 6 in between.
0 is provided at the bottom of the groove.

In addition, a red light emitting LED 10a and a phototransistor 1
1 and between the green light emitting LED 10b and the phototransistor 11, shielding plates 41 and 42 are provided, respectively.
The red and green lights from the red and green LEDs a and 10b are not directly received.

As a result, the red light emitting LED 10a, the green light emitting light 1, and the ED
Since the iOb and the phototransistor 11 can be placed on the same side, the height of the device can be reduced.

FIG. 9 shows fifth and sixth actual IM examples to which the third embodiment is applied.

Figures 9(a) and 9(b) show a red light emitting LED and a green light emitting LED.
A two-color reflective multi-emission L that houses both in the same case.
This is an example using ED. This further facilitates the installation and allows the printing start position to be accurately defined.

Furthermore, although the phototransistor 11 is used in this embodiment, a photodiode may also be used.

(G) Effects of the Invention According to the present invention, when the first and second light sources irradiate each ink layer with light of different predetermined wavelengths, and the light from the first and second light sources passes through each ink layer, The first one outputs a detection signal. Since the second light receiving elements are respectively arranged and the ink layer of each color is discriminated based on the detection signals of the first and second light receiving elements, the desired ink layer can be placed at the printing start position without providing a bar code on the ink sheet. I can cue up. Therefore, the process of coloring and coating the barcode becomes unnecessary, and the width of the ink sheet can be reduced, so the ink sheet can be made smaller and the ink sheet can be manufactured at a lower cost.

Furthermore, since the first light source and the first light receiving element f and the second light source and the second light receiving element are arranged at intervals in the direction perpendicular to the transport direction of the ink sheet, it is possible to accurately define the printing start position. .

Furthermore, according to the present invention, the first and second light sources emit 110 lights of different predetermined wavelengths onto each ink layer; Second
A light source driving means for driving the light sources alternately, and a light receiving element that outputs a detection signal when the light from the first and second light sources respectively passes through the ink layer are provided, and the ink layer of each color is detected by the detection signal of the light receiving element. This makes it easy to attach the light source and the light-receiving element, and it is also possible to accurately define the printing start position.

[Brief explanation of drawings]

FIG. 1 is a circuit configuration diagram showing a first embodiment of the present invention, FIG. 2 is a plan view of an ink ribbon according to the present invention, FIG. 3 is a diagram showing transmittance spectral characteristics of each color ink layer, and FIG. 4 5 is a diagram showing the spectral characteristics of a red light-emitting LED and a green light-emitting LED, FIG. 5 is a diagram showing a $2 embodiment in which the first embodiment is applied, and FIG. 7 is a timing chart showing the circuit operation of the third embodiment, FIG. 8 is a diagram showing the first embodiment applying the third embodiment, and FIG. 9 is a timing chart showing the circuit operation of the third embodiment. FIG. 10 is a plan view showing a conventional ink sheet. l...Platen 3...Recording paper 5...To thermal l'F:G...Ink sheet 8...Motor 1
Light emitting L IE D I Ob-・Green light emitting LED Il
a, 11b, 33...Phototransistor 1. =4.
37... Ink layer discrimination means 30... Light source driving means 0a... Red

Claims (3)

[Claims] (1) An ink sheet in which ink layers of multiple colors are provided in a predetermined color order, and a thermal transfer color that prints color onto recording paper via the ink layers of each color by heating the ink sheet with a thermal head. In the printer, a first light source that irradiates each ink layer with light of a predetermined wavelength;
a second light source that irradiates each of the ink layers with light of a predetermined wavelength different from that of the light source; a first light receiving element that outputs a detection signal when the light from the first light source passes through each of the ink layers; a second light receiving element that outputs a detection signal when light from two light sources passes through each of the ink layers; and an ink layer discrimination means that discriminates the ink layer of each color based on the detection signals of the first and second light receiving elements. A thermal transfer color printer characterized by having: (2) The first light source and the first light receiving element, and the second light source and the second light receiving element are arranged at intervals in a direction perpendicular to the transport direction of the ink sheet. A thermal transfer color printer according to claim 1. (3) An ink sheet in which ink layers of multiple colors are provided in a predetermined color order, and a thermal transfer color that prints color onto recording paper via the ink layers of each color by heating the ink sheet with a thermal head. In the printer, a first light source that irradiates each ink layer with light of a predetermined wavelength;
a second light source that irradiates each ink layer with light of a predetermined wavelength different from that of the light source; a light source driving means that alternately drives the first and second light sources; A thermal transfer color printer comprising: a light-receiving element that outputs a detection signal when the ink passes through each ink layer; and an ink layer discrimination means that discriminates the ink layer of each color based on the detection signal of the light-receiving element.