JPH04348980A - Inking device for thermal transfer printer - Google Patents

Abstract

PURPOSE:To carry out high speed recording which is high in economical efficiency by a method wherein after removing ink of a blanked transfer part on an ink film surface, a specific quantity of an ink film is applied again to the whole ink film surface. CONSTITUTION:An ink film 100 generated in a blanked transfer part of an ink film by transfer with a thermal head (a heater 108) is brought into contact with a cleaning roll 101a, and ink 103 in the blanked transfer part on a surface is dissolved to be removed. Then, by reapplication of a specific quantity of an ink film to the whole surface of the ink film 100 with an applicator roll 106, the ink film 100 which is smooth on the surface of the ink film and is uniform in thickness of the ink film is reproduced, and the ink 103 can be effectively transferred to recording paper. Thereby, high speed recording which is high in economical efficiency can be carried out.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inking device for repeatedly reproducing an ink carrier in a printer using a thermal transfer recording method.

0002

2. Description of the Related Art Conventionally, the basic structure of a thermal transfer recording type line printer capable of recording on plain paper using a thermal head is as shown in FIG. An ink ribbon 401 coated with an ink with a relatively low melting point, such as a binder material such as ester wax with a colorant such as a pigment added thereto, is passed from a pre-wound reel A402 to a heating resistor via a guide roller 404. are sandwiched between the thermal head 118 and the paper 121 arranged in series, and while applying an appropriate pressure between the platen 120 and the thermal head 118, the heating resistor is activated in response to the print signal applied to the thermal head 118. It is heated to melt and transfer the ink on the ink ribbon 401 for recording, and the recorded ink ribbon is wound onto a reel B403. Further, such a thermal transfer recording method has the feature that printing can be performed not only on plain paper but also on resin-based materials such as polyester such as OHP film as a recording medium.

0003

The conventional thermal transfer recording type printer described above has a drawback in that the ink ribbon 401 cannot be used again after the ink has been transferred to the recording medium. Furthermore, there is an uneconomical aspect in that ink remains on the ink ribbon 401 other than the thermally transferred portion and is discarded without being used. There was a challenge to make it. Also, a reel B for winding up the ink ribbon 401 is provided.
403 is required, and a space for providing reel A 402 and reel B 403 is required inside the device, which also causes the problem of increasing the size of the printer.

[0004] Furthermore, characters printed on a used ink ribbon remain in an inverted form, which can be easily identified by a third party, which poses a problem in terms of confidentiality. Another drawback is that the number of characters that can be printed at one time is extremely small compared to other printing methods such as wire dot printers. These problems pose a problem in that the operating cost of using a thermal transfer printer becomes extremely high.

In contrast, the ink ribbon is replaced with a heat-resistant and durable belt-shaped ink carrier, ink is supplied to it, the ink is transferred to the recording medium by a thermal head, and after the transfer, the ink is transferred to the ink carrier again. By storing ink, the above problem is solved.

[0006] As a means to solve this problem,
There are devices disclosed in Japanese Patent Laid-Open No. 2-48594 and Japanese Patent Application Laid-open No. 62-56177, both of which use an ink supply device in which an ink holder is immersed in a large ink container or a rotating roller is immersed in the ink supply device. Ink is supplied to the ink holding body by sandwiching it between pressure rollers, and excess ink is scraped off with a knife edge. However, since these inking devices have a pressure roller and a knife edge, an unnecessarily large load is applied when the ink holder is moved, and a relatively large ink container is required for immersion. , and there were restrictions on their placement, creating a major problem in putting the printer into practical use.

An object of the present invention is to provide an inking device for a thermal transfer printer that solves the above-mentioned conventional problems.

[0008]

[Means for Solving the Problems] The present invention provides an inking device for a thermal transfer printer for repeatedly reproducing and using an endless ink film coated with heat-melting ink in a thermal transfer printer. An ink tank storing melted hot-melt ink, and a heat-resistant material provided on the ink tank with an uneven surface to facilitate removal of the ink film, and the ink film travels in the direction of travel. A cleaning roll that rotates in the forward direction at a peripheral speed higher than the feeding speed of the ink film, a doctor roll that rotates in synchronization with the peripheral speed of the cleaning roll and regulates the ink film on the surface of the cleaning roll, and an applicator roll that rotates at a circumferential speed of 1/2 or less of the feeding speed of the ink film in a direction opposite to the running direction;
A pickup roll is provided which supplies ink while rotating in synchronization with the applicator roll and regulates the height of the ink film on the surface of the applicator roll.

Further, in the present invention, the cleaning roll may be configured to rotate in a direction opposite to the running direction of the ink film at a circumferential speed of 1/2 or less of the feeding speed of the ink film, and the doctor roll may be It may be replaced with a doctor blade made of a thin plate.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

Cross-sectional views of first and second embodiments of the inking device of the present invention are shown in FIGS. 1 and 2.

First, in the ink tanks 102 in the inking devices 111a and 111b heated by the heater 108, which is a heat generating means, a heat-fusible material that is solid at room temperature, such as a binder material such as ester wax, is colored with a pigment or the like. The ink pellets 109 are made of ink with a relatively low melting point of around 80° C.
The ink 103 is melted by the heat of the heater 108 and stored at the bottom of the ink tank 102 . Rotatable cylindrical cleaning rolls 101a and 101b made of a material with relatively high thermal conductivity, such as aluminum, are provided above the ink tank 102, and the length thereof is longer than the width of the ink film 100. Make it small and the same or larger than the recording width. Further, the surfaces of the cleaning rolls 101a and 101b are treated to have a matte finish by sandblasting, etching, or the like. Further, as another embodiment, a linear narrow groove or a spiral narrow groove may be formed along the length direction over the entire outer peripheral surface of the cleaning rolls 101a and 101b.

Doctor rolls 104a and 104b, which rotate in contact with the cleaning rolls 101a and 101b and have the same length as the cleaning rolls 101a and 101b, are provided at the positions shown in the figure. The doctor rolls 104a and 104b are the cleaning roll 101a.
, 101b.

In another embodiment, the doctor roll 104
In place of doctor blades 114a and 104b, doctor blades 114a and 11 are made of thin plates as shown in FIGS.
4b. That doctor blade 114
a, 114b and cleaning rolls 101a, 101b
The cleaning effect is best when the angle θ is at right angles to the
It is desirable that the angle is in the range of ~45°. In order to achieve this operation, the surfaces of the doctor rolls 104a and 104b,
Or the plate material of the doctor blades 114a, 114b is
For example, it is desirable to be made of a heat-resistant, abrasion-resistant, and thermally conductive elastic material such as silicone rubber.

Now, the ink film 1 to which tension has been applied in advance
00 is brought into contact with cleaning rolls 101a and 101b as shown in FIGS.
Since the ink film 100 is rotated at a speed exceeding 0, the ink on the ink film 100 is melted and simultaneously scraped off and removed by the unevenness or grooves on the surface of the cleaning roll 101a. Practically speaking, it is desirable that the circumferential speed of the ink film 100 be at least 1.5 times the traveling speed of the ink film 100.

Further, in the second embodiment, the cleaning roll 101b is
Since the circumferential speed of the ink film 100 is less than 1/2 of the speed of the ink film 100 and it is being rotated in the opposite direction, the ink film 1
At the same time as the ink on the cleaning roll 101b is melted, it is scraped off and removed by the unevenness or grooves on the surface of the cleaning roll 101b. Practically speaking, the circumferential speed is preferably in the range of 1/2 to 1/10 of the traveling speed of the ink film 100. In addition, since these operations are considered to be a pretreatment stage of inking, the ink film 10 is not necessarily
It is not necessary to remove all the ink on 0.

The ink scraped off from the ink film 100 and adhered to the cleaning rolls 101a and 101b is collected into the ink 103 in the ink tank 102. In addition, the ink tank 102 can also be removed by doctor rolls 104a, 104b or doctor blades 114a, 114b.
will be collected within. Next, the ink film 100 from which the ink has been removed is brought into contact with the applicator roll 106 by a backup roller 105 provided in the film cartridge 110 and also serving as a return roller. The applicator roll 106 is made of a metal material such as stainless steel or aluminum and subjected to chromium plating to have a smooth and durable surface, and rotates in the opposite direction to the running direction of the ink film 100. The peripheral speed is preferably in the range of 1/2 to 1/10 of the running speed of the ink film 100. The number is the target thickness of the coating film on the ink film 100 (5
15 μm), the viscosity and surface tension of the ink 103,
It is determined by parameters such as the traveling speed of the ink film 100. Further, a pickup roll 107 is provided above the ink tank 102 adjacent to the position shown in the figure below the applicator roll 106 to apply and supply an appropriate amount of ink. The ink uniformly applied to the surface of the applicator roll 106 by the pickup roll 107 is transferred to the ink film 100 by coming into contact with the ink film 100. Further, the applicator roll 106 is oriented in the opposite direction to the ink film 100.
Since the ink film is rotated at a low speed, the ink film can be smoothed, and an ink film of completely uniform thickness is formed parallel to the surface of the ink film 100. Therefore, uneven transfer due to non-uniformity of the ink film does not occur during recording.

Practical examples of printers using the inking devices shown in the first and second embodiments described above are shown in FIGS. 4 and 5. First, the ink film 1 shown in FIG. 5(b)
00 is prepared, and as shown in the cross-sectional view of FIG.
00 denotes the backup roller 105 described above, the tension roller 204 that applies a predetermined tension to the ink film 100 by the tension spring 205, and the guide roller 202.
, and a return roller 203. In addition, the housing 201 of the film cartridge 110 has a
As shown in (b), a platen opening 206 is provided on the top surface, a thermal head opening 207 is provided on both sides, and an inking opening 208 is provided on the bottom surface.

The film cartridge 110 is mounted on a frame 210 as shown in the sectional view of the printer in FIG.
11 are provided. The ink film 100 in the film cartridge 110 is moved by a motor (not shown) provided in the frame 210 in synchronization with the paper 121 that is fed between the platens 120 . The portion of the ink film 100 that has been recorded and transferred onto the paper 121 by the thermal head 118 and has consumed ink passes through the inking device 111 via a return roller 203, a guide roller 202, and a tension roller 204, where it is transferred as shown in FIGS. 1 and 2. Ink film 100 as described
is reproduced and returned to the position of the thermal head 118 again to record and transfer onto paper.

It should be noted that the above description of the embodiment of the inking device 111 does not describe the limitations of the embodiment depending on the recording format of the printer, ie, serial printer, line printer, etc., but the embodiment may be applied to different recording formats. It is clear that the object of the present invention can be achieved even if the configuration is changed.

[0021]

As explained above, the present invention brings an ink film, which has been transferred by a thermal head and has a transfer omission part, into contact with a cleaning roll.
After dissolving and removing the ink in the transfer areas on the surface, a predetermined amount of ink film is reapplied to the entire surface of the ink film using an applicator roll, thereby making the surface of the ink film smooth and thick. A uniform ink film is regenerated, the problems of economic efficiency and printing speed of conventional thermal transfer printers are solved, and an economically efficient printer capable of high-speed recording that can efficiently transfer ink to recording paper is obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a sectional view showing a second embodiment of the invention.

FIG. 3 is a cross-sectional view showing another embodiment of the main part of the present invention, where (a) is a diagram corresponding to the first embodiment, and FIG. 3 (b) is a diagram corresponding to the second embodiment. be.

FIG. 4 is a sectional view of a printer using the first and second embodiments.

FIG. 5 is a diagram showing a film cartridge used in the printer of FIG. 4, with FIG. 4(a) being a sectional view and FIG. 5(b) being a perspective view.

FIG. 6 is a side perspective view showing the configuration of a conventional thermal transfer line printer.

[Explanation of symbols]

100 Ink film 103 Ink 101a, 101b Cleaning roll 104
a, 104b Doctor roll 114a, 114
b Doctor blade 105 Backup roller 106 Applicator roll 107 Pickup roll 108 Heater 109 Ink pellet 110 Film cartridge 111, 111a, 111b Inking device 1
18 Thermal head 121 Paper

Claims (3)

[Claims] [Claim 1] In an inking device for a thermal transfer printer for repeatedly recycling and using an endless ink film coated with a thermofusible ink in a thermal transfer printer, the thermofusible ink is heated and melted in advance by a heat generating means. The ink tank is provided on top of the ink tank and is made of a heat-resistant material with an uneven surface so that the ink film can be easily removed. a cleaning roll that rotates at a peripheral speed higher than the feed speed of the cleaning roll, a doctor roll that rotates in synchronization with the peripheral speed of the cleaning roll and regulates the ink film on the surface of the cleaning roll, and a doctor roll that rotates in a direction opposite to the running direction of the ink film. An applicator roll that rotates at a circumferential speed of 1/2 or less of the feed speed of the ink film, and an applicator roll that supplies ink while rotating in synchronization with the applicator roll and regulates the height of the ink film on the surface of the applicator roll. 1. An inking device for a thermal transfer printer, comprising a pickup roll. 2. The thermal transfer printer according to claim 1, wherein the cleaning roll rotates in a direction opposite to the running direction of the ink film at a circumferential speed of 1/2 or less of the feeding speed of the ink film. inking device. 3. The inking device for a thermal transfer printer according to claim 1, wherein the doctor roll is replaced with a doctor blade made of a thin plate.