JPH09187977A - Thermal transfer printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve recording using a thermally sublimable ink ribbon and to keep the life of a thermal head and that of an ink ribbon long by performing the recording of one dot by the supply of a current to respective heating elements by the supply of a current divided into a plurality of times. SOLUTION: A mode discrimination part 27 discriminates a first recording mode performing recording by hot melt transfer to plain paper by using a hot-melt ink ribbon or a second recording mode performing recording by thermal sublimation to exclusive paper by using a thermally sublimable ink ribbon. A second recording mode control part 29 divides energy necessary for the transfer of thermally sublimable ink of one dot into a plurality of pulses to supply the same to a heating element to which a current must be supplied. That is, the supply of a current at every one dot to the heating elements of a thermal head 7 is constituted, for example, of divided pulses P1-P5 and the interval between a pair of pulses at adjacent positions is set so as to become mutually equal so that the current supply times of the pulses P1-P5 become mutually equal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer printer for recording by transferring the ink of an ink film to a paper by selective heat generation of a heating element of a thermal head, and more particularly to a silver lead photograph using a special paper. The present invention relates to a thermal transfer printer capable of performing recording with comparable high image quality.

[0002]

2. Description of the Related Art In general, the thermal transfer printer supports a sheet in front of a platen and also mounts a thermal head having a plurality of heating elements on a carriage, and mounts a thermal head on the substrate between the thermal head and the platen. An ink ribbon, which is an example of an ink film coated with a desired ink, and the paper are sandwiched, and while the thermal head is reciprocally moved along with a carriage along a platen, the ink ribbon is fed out, and a heating element of the thermal head is recorded. An image such as a desired character is recorded on a sheet by selectively causing heat to be generated based on information. Such thermal transfer printers are frequently used as output devices such as computers and word processors because of high recording quality, low noise, low cost, and ease of maintenance.

A conventional thermal transfer printer of this type is one that records on paper using an ink ribbon (thermofusible ink ribbon) in which a fusible ink is applied to a substrate such as a plastic film. Although it is known, there is also known one in which recording is performed on a sheet using an ink ribbon (thermally sublimable ink ribbon) having a substrate coated with thermally sublimable ink.

Of these, a thermal transfer printer for recording on paper using a heat-meltable ink ribbon (hereinafter referred to as a heat-melting type thermal transfer printer) is capable of recording on a wide variety of papers such as plain paper, cardboard and postcards. It is easy to use and has excellent usability.

On the other hand, a thermal transfer printer (hereinafter referred to as a thermal sublimation type thermal transfer printer) for recording on a sheet by using a thermal sublimation ink ribbon uses silver-lead paper using a surface-treated special paper. It is possible to obtain a high quality recorded image comparable to a photograph.

[0006]

By the way, in order to perform recording using the thermal sublimation ink ribbon, the energy applied to the heating element of the thermal head is compared with the case where the thermal melting ink ribbon is used. Since the size must be increased, if the same heating element is continuously energized, there is a risk that the thermal head in this portion may be damaged or the ink ribbon may be cut due to the high temperature.

In view of the above-mentioned points, the present invention provides a thermal transfer printer which can perform good recording by using a thermal sublimation ink ribbon and can maintain a long life of the thermal head and the ink ribbon. The purpose is to do.

[0008]

In order to achieve the above-mentioned object, the thermal transfer printer according to the present invention is characterized in that the 1-dot recording by energizing each heating element is divided into a plurality of energizations. It has a control means for performing By employing such a configuration, it is possible to apply energy required for recording to each heating element while maintaining a temperature that does not damage the thermal head and the ink ribbon.

Further, a feature of the thermal transfer printer of the present invention according to claim 2 is that the divided energization times are made equal to each other. Further, by adopting such a configuration, it is possible to equally divide the energy and maintain a good temperature for recording to the extent that the thermal head and the ink ribbon are not damaged.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows an embodiment of the present invention in which a thermal sublimation ink ribbon and a thermal melting ink ribbon can be selectively used. In the thermal transfer printer 1 of the present embodiment shown in FIG. 3, a platen platen 2 is arranged at a desired position of a frame (not shown) so that its recording surface 2a is substantially vertical. A guide shaft 3 is disposed below the front side of the plate 2 in parallel with the platen 2. And
Vertically divided carriages 4 are attached to appropriate positions of the guide shaft 3, and one carriage 4a shown below is a lower carriage attached to the guide shaft 3 and the other carriage 4a shown above. The carriage 4b is an upper carriage to which a ribbon cassette 5 described later is attached and which can be vertically contacted with and separated from the lower carriage 4a.

In the carriage 4, a suitable drive belt 6 wound around a pair of pulleys (not shown) is driven by a drive means (not shown) such as a stepping motor to cause the guide shaft 3 to move. It is designed to be reciprocally driven along it. The carriage 4 can be moved by a control unit 25, which will be described later, in either a high speed or a low speed.

A well-known head moving mechanism (both not shown) facing the platen 2 and capable of operating with the driving force of a drive motor with respect to the platen 2 can be brought into and out of contact with the platen 2. A thermal head 7 is provided for recording on a sheet (not shown) on the platen 2 in a pressure contact state (head-down state) in which the sheet is in contact with the sheet. The thermal head 7 has a plurality of heating elements (not shown) arranged and arranged to selectively generate heat based on desired recording information input by an appropriate input device (not shown) such as a keyboard. It has. The thermal head 7 is controlled by a control unit 25 described later.
The pressing force on the platen 2 can be selected from either strong pressing or weak pressing, and the thermal head 7
One of two stages of large and small heat energy (specifically, two stages of a long time and a short period of time for energizing the heating element) can be selected.

The carriage 4 will be described in more detail. In the carriage 4, a plate-shaped upper carriage 4b which is substantially parallel to the upper surface of the lower carriage 4a attached to the guide shaft 3 is moved by the parallel crank mechanism 8 to the lower carriage 4a. It is attached so as to be movable in parallel so as to come into contact with and separate from. As shown in FIG. 3, a pair of the parallel crank mechanisms 8 is provided at both left and right ends of the carriage 4,
It has a pair of links 9a and 9b crossing each other in an X shape, and the crossing position of these links 9a and 9b is
a and the ends of the links 9a, 9b
The lower carriage 4a and the upper carriage 4b are slidably locked by long holes (not shown) formed at the upper end portions on the left and right sides of the upper carriage 4b by b, 10c, 10d, and 10e, respectively.

A rotary crank mechanism 11 is arranged on the lower carriage 4a, and the rotary crank mechanism 11 allows the upper carriage 4b to move in parallel. This rotary crank mechanism 11
A rotating plate 12 serving as a rotating member supported to be rotatable and driven by the lower carriage 4a, and a connecting link 14 serving as a connecting member pivotally connected to an eccentric position of the rotating plate 12 by a pin 13a. The front end 14 is pivotally connected to the upper carriage 4b by a pin 13b.
Then, the rotating plate 12 is rotatably driven by a suitable driving means (not shown) such as a motor.

Returning to FIG. 1, plate-shaped arms having engaging portions 15a on both left and right sides of the upper carriage 4b, the tips of which are gently curved inwardly and projections are formed on the upper and lower ends thereof. Numerals 15 stand upright at an interval substantially equal to the width of the ribbon cassette 5. A pair of rotatable bobbins 16 are disposed at a central portion of the upper carriage 4b so as to protrude upward at a predetermined interval from each other.
The bobbin 16 allows the ink ribbon 17 to travel in a predetermined direction. One of the pair of bobbins 16 is a take-up bobbin 16 a for winding the ink ribbon 17, and the other is a delivery bobbin 16 for sending the ink ribbon 17.
It is assumed to be b. An optical sensor 18a is disposed on the edge of the carriage 4 farther from the platen 2 as a sensor 18 for detecting the type of the ink ribbon 17 stored in the ribbon cassette 5. This optical sensor 1
In this embodiment, a reflection type is used as 8a. The optical sensor 18a is connected to a control unit 25, which will be described later, which controls a recording operation and the like of the thermal transfer printer 1 disposed at a desired position of the thermal transfer printer 1.

As shown in FIGS. 1 and 2, above the carriage 4, there is provided a substantially plate which is openably and closably supported by a frame (not shown) at an appropriate interval as shown by a double-headed arrow A in FIG. A canopy 19 having a shape is arranged. The canopy 19 functions as a paper presser on the exit side of a paper feed mechanism (not shown) in the closed state, and is disposed so as to face the carriage 4. The length is almost the same.

A plurality of cassette holders (not shown) for holding the ribbon cassettes 5 are provided at predetermined positions on the lower surface of the canopy 19 which faces the carriage 4 in parallel, and a plurality of cassette holders are provided by the cassette holders. In the embodiment, the ribbon cassette 5a in which the ink ribbon (heat-melting ink ribbon) 17a coated with the heat-meltable ink is housed, and the ink ribbon coated with the heat-sublimable ink (heat-sublimable ink ribbon ) 17b and a ribbon cassette 5b having the inside accommodated therein are arranged in a line in the moving direction of the carriage 4. Then, the ribbon cassettes 5a and 5b are operated by the parallel crank mechanism 8 which operates together with the rotary crank mechanism 11, as indicated by a double-headed arrow B in FIG.
b is selectively exchanged with b.

Each ribbon cassette 5a, 5 of this embodiment
b is a rotatable support (not shown), which is formed in a pair of upper and lower, substantially rectangular case bodies 20, all of which have the same shape and the same size regardless of the type of the ink ribbon 17. A pair of reels, a pair of rotatably supported ribbon feed rollers, a plurality of guide rollers facing the rotatably supported ribbon path, and the like are provided. The ink ribbon 17 is provided between a pair of reels.
Is wound, and an intermediate portion of the ink ribbon 17 is led out. When the ribbon cassette 5 is mounted on the upper carriage 4b, one of the pair of reels serves as a take-up reel for winding the ink ribbon 17 of the portion used for recording, and the other sends out the ink ribbon. It is a sending reel. On the inner peripheral surface of each reel, a plurality of key grooves are formed in a spline shape at intervals in the circumferential direction, and the inner peripheral surface of the take-up reel is formed by the winding bobbin 16a.
Is formed as a take-up hole 21a, and the inner peripheral surface of the delivery reel is provided with a delivery hole 21b with which the delivery bobbin 16b is engaged.
It has been. In addition, the carriage 4 of the ribbon cassette 5
A recess 22 facing the thermal head 7 is formed on a surface facing the platen 2 in a state where the ink ribbon 17 is mounted on the ink ribbon 17.

An identification mark 23 for identifying the type of the ink ribbon 17 accommodated in each ribbon cassette 5 is provided on the rear surface of the ribbon cassette 5 extending in parallel with the surface in which the recess 22 is formed. It is arranged. The identification mark 23 of the present embodiment is formed by a reflective seal 24 having a different number of striped non-reflective portions 24a depending on the type of the ink ribbon 17.

Then, the identification mark 23 is detected by the optical sensor 18a provided on the carriage 4, and the detection signal is output to the control unit 25 of the printer. In the control unit 25, the identification mark 23 of each ribbon cassette 5 is detected. By counting the number, the type of the ink ribbon 17 accommodated in the ribbon cassette 5 is determined.

That is, the ribbon cassette 5a shown on the left side in FIG. 1 is provided with a reflection seal 24A having four non-reflecting portions 24a as an identification mark 23, and the ribbon cassette 5b shown on the right side in FIG. A reflection sticker 24B having two non-reflecting portions 24a is disposed as the identification mark 23. And the ribbon cassette 5
In FIG. 1, the left end of the rear surface shown on the near side is a reference position BP for detecting the identification mark 23, and the identification mark 2
3, the distance L to the right end surface of the non-reflective portion 24a located at the right end is the same for all the identification marks 23, and a desired distance L for identifying the type of the ink ribbon 17 within this distance L. The non-reflection part 24a is formed. The carriage 4 can be stopped when the optical sensor 18a detects the identification mark 23 to be used. When the carriage 4 is stopped, the ribbon cassette 5 stored in the cassette holder is moved to the upper carriage 4b. It has been handed over.

The identification mark 23 may be printed on the ribbon cassette 5 and is not particularly limited to the configuration of this embodiment.

The control unit 25 includes a memory (not shown), C
As shown in FIG. 4, at least the heat-meltable ink ribbon is formed based on a mode signal sent from a mode changeover switch 26, which is formed of PU or the like and is arranged at a desired position of a frame (not shown). A mode for determining whether the first recording mode in which recording by thermal fusion transfer is performed on a sheet such as plain paper using 17a or the second recording mode in which recording by thermal sublimation transfer is performed on dedicated paper by using the thermal sublimation ink ribbon 17b Based on the discrimination result of the discriminating unit 27 and the mode discriminating unit 27, the moving speed of the carriage 4, the energization time to the thermal head 7, the pressure contact force of the thermal head 7 with respect to the platen 2, the ribbon cassette 5, etc. are corresponded to each mode. It has a first recording mode control unit 28 and a second recording mode control unit 29 which are controlled as described above.

By the way, the energy applied to each heating element of the thermal head 7 in order to transfer the ink of the heat sublimable ink ribbon 17b to the dedicated paper is required to transfer the ink of the heat fusible ink ribbon 17a to the paper. Since the energy is larger than the energy, if the electric energy is applied to the heating element of the thermal head 7 to be energized in one pulse, the thermal head 7 becomes too hot, which may cause a problem in durability. Therefore, the second recording mode control unit 29, which controls the second recording mode in which recording is performed by thermal sublimation transfer on special paper using the thermal sublimation ink ribbon 17b,
Energy necessary for transferring one dot of thermal sublimation ink is supplied to a heating element to be energized by dividing the energy into a plurality of pulses.

FIG. 5 shows a specific example of energization of the heating element of the thermal head 7 for each dot by the second recording mode control unit 29. The energization of one dot in this specific example is divided into a plurality of parts. It is composed of (five in this example) pulses P1, P2, P3, P4 and P5. The durations (energization times) of the respective pulses P1 to P5 are set to be equal to each other, and energization for one dot to the heating element is simply divided equally into five. Further, a pair of adjacent pulses P1 and P2 generated by dividing the energization for one dot into five,
The intervals (time) between P2 and P3, P3 and P4 or P4 and P5 are also set to be equal to each other.

The control unit 25, based on the output signal from the optical sensor 18a accompanying the movement of the carriage 4,
The presence or absence of the ribbon cassette 5, the type of the ink ribbon 17 stored in the ribbon cassette 5, the moving distance of the carriage 4 with respect to the home position, the open / close state of the canopy 19, the distance between the ribbon cassettes 5, and the like are determined or detected. I have.

Next, the operation of this embodiment having the above-mentioned structure will be described.

The operation of selecting the recording mode in which the thermal transfer printer 1 of the present embodiment is driven and the recording mode is matched with the recording purpose is selected by the operator.
6 is operated to perform recording by thermal fusion transfer on a sheet such as plain paper using the thermal fusion ink ribbon 17a or recording by thermal sublimation transfer on special paper using the thermal sublimation ink ribbon 17b. This is performed by selecting one of the second recording modes to be performed.

When the recording mode selection operation is performed, a mode signal corresponding to one of the selected modes is sent from the mode changeover switch 26 to the control section 25, and the mode discrimination section of the control section 25. Reference numeral 27 determines whether the mode signal sent from the mode changeover switch 26 is the first recording mode or the second recording mode, and which one of the first recording mode control unit 28 and the second recording mode control unit 29 is based on the determination result. One of them is operated to start the selection operation of the ribbon cassette 5 in which the ink ribbon 17 having the heat-meltable ink or the heat-sublimable ink corresponding to either the first recording mode or the second recording mode is stored.

Then, the carriage 4 located at the home position is moved (run) in response to a command from the controller 25 (more specifically, one of the first recording mode controller 28 and the second recording mode controller 29). Then, the optical sensor 18a arranged on the carriage 4 detects the identification mark 23 of the ribbon cassette 5. And the optical sensor 18a
A unique detection signal of each identification mark 23 based on the arrangement and pitch of the non-reflection portions 24a is sent to the control unit 25, and it is determined whether or not the identification mark 23 corresponds to the instruction issued by the control unit 25. In the case of the identification mark 23 corresponding to the command, the movement of the carriage 4 is stopped, and when the identification mark 23 is not the command corresponding to the command, the movement of the carriage 4 is continued until the identification mark 23 corresponding to the command is detected. That is, in the present embodiment, by detecting the difference in the reflection seal 24 of the ribbon cassette 5 depending on the type of the ink ribbon 17, the ribbon cassette 5
(Specifically, the ink ribbon 17) can be reliably determined.

Then, the thermal transfer printer 1 of the present embodiment
According to this, since each ribbon cassette 5 is attached to a predetermined position of the canopy 19, the distance from the home position of the carriage 4 to the identification mark 23 of each ribbon cassette 5 is set to a constant value, and the carriage 4 with respect to the home position is fixed.
Can be easily detected. That is, a stepping motor (not shown) for driving the carriage 4
By counting the number of steps, the moving distance of the carriage 4 with respect to the home position can be easily detected, and the home position can be easily detected. Then, the step number of the stepping motor corresponding to the distance from the predetermined home position to the identification mark 23 of each ribbon cassette 5 is compared with the actual step number of the stepping motor when the carriage 4 is driven. This makes it possible to detect a change in the thermal transfer printer 1 due to a temperature change such as a change in the distance between the home position and the ribbon cassette 5 and a change in the distance between the ribbon cassettes 5.

Further, according to the thermal transfer printer 1 of the present embodiment, the ribbon cassette 5 is attached to the predetermined position of the canopy 19, so that when the canopy 19 is opened, the ribbon cassette 5 is not opened. The identification mark 23 does not face the optical sensor 18a, and as a result, even if the carriage 4 is scanned, the optical sensor 18a cannot detect the identification mark 23 of the ribbon cassette 5. Using this, the open / closed state of the canopy 19 can be detected.

As described above, according to the thermal transfer printer 1 of the present embodiment, one sensor 18 detects the presence and type of the ribbon cassette 5, the home position, and the open / closed state of the canopy 19. Since it can be used for both, it is possible to reduce the overall cost.

Then, the ribbon cassette 5 containing the ink ribbon 17 corresponding to the selected recording mode therein.
The canopy 19 is moved by the parallel crank mechanism 8 and the rotary crank mechanism 11 as shown by a double-headed arrow B in FIG.
And the upper carriage 4b is selectively transferred, the ribbon cassette 5 is mounted on the carriage 4, and the operation of selecting the ribbon cassette 5 ends.

Then, a sheet corresponding to the selected recording mode is set between the platen 2 and the thermal head 7 manually or by a sheet feeding device (not shown), and the recording operation is started. Then, in the first recording mode, the pressure contact force of the thermal head 7 with respect to the platen 2 in the head-down state is about 0.5 to 3.0 kg in response to a command from the first recording mode control unit 28 of the control unit 25. The thermal head 7 is mounted, the moving speed of the carriage 4 corresponding to the recording speed by the thermal head 7 is controlled to about 10 to 50 cm / sec, and the energization time per dot of the heating element of the thermal head 7 is controlled to about 50 to 2000 μsec. As a result, it is possible to reliably perform recording by thermal fusion transfer on a sheet such as plain paper using the thermal fusion ink ribbon 17a.

In the second recording mode, the pressure contact force of the thermal head 7 with respect to the platen 2 in the head-down state is smaller than that in the first recording mode in response to a command from the second recording mode control unit 29 of the control unit 25. 0.2 ~
The moving speed of the carriage 4 on which the thermal head 7 is mounted is set to about 1.5 kg,
Approximately 25 cm / sec, the same energization P of 5 times by dividing the energization per dot to the heating element of the thermal head 7
Is controlled so as to be repeated, so that the thermal sublimation transfer can be surely performed on the paper by using the thermal sublimation ink ribbon 17b.

As described above, by making the pressure contact force of the thermal head 7 against the platen 2 in the second recording mode weaker than that in the first recording mode, wear of the thermal head 7 in the second recording mode is reduced, and Due to
It is possible to reliably improve the overall durability of the thermal head 7. Further, the moving speed of the carriage 4 in the second recording mode is slower than that in the first recording mode, and the energization per dot to the heating element of the thermal head 7 in the second recording mode is divided into five times. By repeating the same pulse P, the second recording mode in which the heat sublimable ink is sublimated and transferred to the paper, which requires larger thermal energy than the first recording mode in which the heat fusible ink is melted and transferred to the paper Since the recording can be surely performed, it is possible to obtain a high quality recording quality comparable to that of a silver lead photograph.

Further, in the second recording mode, by energizing the heating element of the thermal head 7 per dot by dividing the energization into 5 pulses P and repeatedly supplying them, the thermal head can be simply lengthened. It is possible to reliably prevent the risk that the heat generation temperature of the heat generating element 7 exceeds the allowable temperature and the thermal head 7 is damaged or the ink ribbon 17b is cut. That is, as shown in FIG. 5, when five pulses P are supplied to the heating elements of the thermal head 7 for energizing one dot, the temperature of the thermal head 7 rises each time the pulse P is supplied, but the pulse P Is given intermittently, and the temperature of the thermal head 7 decreases when the pulse P is interrupted. Therefore, the temperature of the thermal head 7 always repeats vertical movement within the allowable temperature. In particular, by making the time and interval of each pulse P equal, the maximum temperature and the minimum temperature of the thermal head 7 can be made substantially equal for each pulse P.

Further, the thermal transfer printer 1 of the present embodiment
Is a first recording mode in which recording is performed by thermal fusion transfer on various types of paper by using the thermal fusion ink ribbon 17a by switching the mode changeover switch 26 according to the recording purpose, and the thermal sublimation ink ribbon 17b. Since it is possible to easily select the second recording mode for performing high-quality recording comparable to a silver lead photograph by thermal sublimation transfer on a dedicated paper and perform recording, a single thermal transfer printer 1 can be used to print on paper. It is possible to surely perform general recording and recording of a high-quality recorded image comparable to a silver lead photograph, and it is possible to reliably reduce the installation space as compared with the conventional case.

The present invention is not limited to the above-mentioned embodiments, but can be modified as necessary. For example, the number of times of dividing the energization of one dot to the heating element is not limited to the five in the embodiment, but may be divided into other numbers. Further, it is also possible to perform good recording using the thermally sublimable ink ribbon without making the energization times of the divided pulses equal to each other.

[0041]

As described above, according to the thermal transfer printer of the present invention, good recording can be performed by using the thermally sublimable ink ribbon, and the long life of the thermal head and the ink ribbon can be maintained. The effect of being able to do is possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of a thermal transfer printer according to the present invention.

FIG. 2 is a schematic side view showing a main part of the thermal transfer printer of FIG.

3 is a schematic side view of a carriage of the thermal transfer printer of FIG.

FIG. 4 is a block diagram showing the configuration of a control system of the thermal transfer printer of FIG.

5 is a graph showing the state of each pulse and the temperature of the thermal head in the second recording mode using the thermal sublimation ink ribbon in the thermal transfer printer of FIG.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 thermal transfer printer 2 platen 4 carriage 5 ribbon cassette 5a (ink ribbon coated with hot melt ink is stored inside) ribbon cassette 5b (ink ribbon coated with heat sublimation ink is stored inside) Ribbon cassette 7 Thermal head 17 Ink ribbon 17a Ink ribbon 17b (to which heat-meltable ink is applied) Ink ribbon 17b (to which thermal sublimation ink is applied) 25 Control unit 26 Mode switch 27 Mode discriminator 28 First recording mode Control unit 29 Second recording mode control unit P pulse

Claims (2)

[Claims] 1. A thermal sublimation ink film is formed by driving a heating element of the thermal head while moving the thermal head having a plurality of heating elements formed on the platen via an ink film and a paper while being pressed against the platen. A thermal transfer printer for transferring ink to a sheet for recording, wherein the thermal transfer printer has a control means for performing recording of one dot by energizing each of the heating elements by energization divided into a plurality of times. 2. The thermal transfer printer according to claim 1, wherein the energization times of the divided times are made equal to each other.