JPS60220756A - Discharge type non-impact printer - Google Patents

Abstract

PURPOSE:To raise the density of printing as well as the quality of printing by a method in which a workable and indestructible ink roller is produced by increasing the areas of an insulating partition, and the staining of discharge head is eliminated by easing the discharge conditions. CONSTITUTION:The areas of an insulating partition 104e formed of enameled plate are greatly widened by using the arrangement of recessions 104a, as shown in Fig. The groove 104g of a base 104f formed of copper is also widened, making etching and enameling processes easier. The receiving area of doctor blade is also greater and the insulating partition 104e becomes safe against greakage. The discharge timing from the discharge electrode 109b to the recessions 104a is before the recessions 104a go to below the discharge electrode 109b. Since nothing but the subject recessions 104a is in the neighborhood of the electrode 109b, no striking of other dots by misdischarge occurs, and also since the discharge head 9 is not covered on the recessions 104a, no staining occurs.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an improvement in a non-impact printer that utilizes a discharge phenomenon that does not require discharge recording paper, thermal transfer ink film, specially molded ink, etc. be.

[Background of the invention]

As non-impact printers that are noiseless and suitable for color printing, inkjet printers that eject liquid ink and thermal transfer printers are popular, but the former requires the use of dye-based ink, making it difficult to print colors. It is not very clear, and measures need to be taken to prevent clogging. The latter uses a large amount of relatively expensive thermal transfer film and is disposable, so running costs are high and the machine is difficult to downsize.

[Conventional technology and problems]

The configurations shown in FIGS. 1 to 4 were considered as an intermediate system that takes advantage of the features of these two systems. FIG. 1 is a perspective view showing the overall configuration, FIG. 2 is a side view, FIG. 3 is an enlarged plan view of the main part, and FIG. 4 is an enlarged side view of the main part. The ink 1a, which is solid at room temperature, is put into an ink tank 6 equipped with a heater 2, melted, and applied onto an ink roller 4, which has a dense recess 4a formed on its outer periphery, lifted, and installed by fixing one end in the middle. Ink 1 enters the recess 4a with a certain doctor blade 5.
Scrape off everything except b. Paper feed roller 6 and auxiliary roller 7
Between the paper 8 being wound up by the ink roller 4 and the ink roller 4, there is a discharge electrode 9b formed on an insulating member 9a, and a driving voltage from the drive circuit 10 is applied based on one character or image signal.
Then, a discharge occurs from the corresponding discharge electrode 9b to the corresponding recess 4b, causing the ink 1b to fly and print on the paper 8.

This method allows the use of colorful pigments, eliminates the risk of clogging, eliminates the waste of ingots and film, and has the characteristics of producing gradations by controlling the current application time.

However, there are some points that need improvement in detail.

The first is the processing and breakability of the insulating partition 4e between the recess 4C and the recess 4d of the ink roller 4. In order to increase the printing density of the tod, the thinner the insulating partition portion 4e is, the better. In terms of material, glass thread is suitable in terms of insulation, heat resistance, and abrasion resistance, but it is easy to break because of the pressure exerted by the doctor blade 5. Furthermore, forming the mesh-like groove 4g in the base metal part 4f and creating the insulating partition part 4e with the base mesh inserted into the groove 4g are performed by wire discharge and rolling. The second problem is that the accuracy of the position of the discharge electrode 91) relative to the recess 4C of the ink roller 4 and the accuracy of the timing of discharge are very strict. In other words, if the position of the discharge electrode 9C is not appropriate in FIG.
C and 4d) also discharge at the same time and hit the wrong dot. The third is that the discharge nozzle 9 is easily contaminated;
This means that the density of the printed image becomes uneven.

That is, as shown in FIG. 4, in order to avoid discharge to the wrong position, discharge should occur at a position where the discharge electrode 9C approaches the recess 4h for one purpose. For this reason, the ink 1C that flies up hits the discharge head 9 and becomes a stain, and the color of the portion of the printed dot that is in the shadow of the discharge head 9 becomes lighter.

[Purpose of the invention]

The present invention was developed in view of the problem of warping, and it is possible to provide an ink roller 4 that is easy to work and hard to break, eases discharge conditions, eliminates stains on the discharge head, and improves print quality and print density. This is what we are trying to measure.

[Structure of the invention]

In order to achieve the above object, one is that the density of the recesses 4a on the ink roller 4 is reduced, and the second is that the discharge head 9 is set to discharge at a position where it does not come into the corresponding recess 4a. That's what I did.

[Embodiments of the invention]

The present invention will be described in detail below based on the drawings.

5 to 7 show a first embodiment of the present invention, and FIG. 5 shows a recess 104a on the ink roller 104 and a discharge pole 109b.
FIG. 6 is a side view of FIG. 5, and FIG. 7 is a perspective view of the device according to the present invention.

Regarding FIG. 5, the arrangement of the recesses 104a is as follows: from the arrangement in FIG. 3, the first row is thinned out every other row, the second row is all removed, and the third row is one row after the first row. They are arranged every other time. For this reason, the area of the insulating partition portion 104e made by enameling is greatly expanded. Therefore, the grooves 104g and 1 of the base portion 104 made of copper are also widened.

Etching and enameling (σ) processing are also easier.

The area for receiving the doctor blade 5 is also large, making it safe from damage to the insulating partition 104e.

Next, regarding the timing of discharge from the discharge electrode 109b to the recess 104a, as shown in FIG. 6, the discharge occurs before the recess 104a enters under the discharge electrode 109b. As seen in FIG. 5, the target recess 1 is located near the discharge electrode 109b.
Since there is no other than 04a, there is no need to worry about hitting another dot due to one wrong discharge. Furthermore, since the discharge head 9 does not extend over the recesses 10 and 4a, there is no possibility of staining with the ink 104h or uneven dot shading.

8 and 9 show other embodiments, FIG. 8 being an enlarged plan view of the main part, and FIG. 9 being a side view of the main part.

FIG. 8 shows the row arrangement pitch P1 of 2 of IJ of the recess 204a.
It's worth twice as much. This corresponds to eliminating the insulating partition part 4e in the case of FIG. The adjacent discharge electrodes 209d are arranged in the vicinity of each other and have a row arrangement pitch P.
2 is constructed at a position shifted by the same amount of g.

Regarding the above example 0) modification, one discharge henode 9
The mounting direction for the ink roller 4 may be opposite to that shown in FIG. 2, and may be configured to be inserted from the left side in the drawing. The shape of the concave portion 104a of the ink roller 104 is not a square, but may be any shape that can form a dot, such as a rectangular shape, a triangular polygon, or a star shape. Furthermore, if it is preferable for the dots to have a somewhat shaped shape, such as in the case of a single letter, the pitch may be set to be smaller than twice the width of the recessed portion 204a. In order to obtain gradations, in addition to changing the discharge voltage or modulating the energization time, it is also possible to overprint ink onto a plurality of concave portions θ) for one dot. In the case of color printing, ink rollers for the three primary colors or black may be arranged side by side, or the ink rollers may be alternated. The printing speed can be made exactly the same as the conventional example by increasing the number of rotations of the ink roller. The insulating partition of the ink roller may be made of enameled glass, ceramic, or the like.

〔Effect of the invention〕

As described above, according to the present invention, since the area of the insulating partition is increased, the grooving process for fixing the insulating partition to the ink roller and the construction of the insulating partition σ) become easier. Also, since the strength of the insulating partition increases, there is less worry about damage during processing and use. Since the head does not overlap with the recess, there is no head dirt and the quality of each dot is improved. Proximity discharge is eliminated, so discharge to the wrong position is also eliminated. Since the zero pitch between recesses can be shortened, higher density printing than before is possible.

[Brief explanation of the drawing]

Figures 1 to 4 show conventional examples. Figure 1 is an overall perspective view.
FIG. 2 is a side view showing the overall configuration; FIG. 3 is an enlarged plan view of the main parts; and FIG. 4 is an enlarged side view of the main parts. 5 to 7 show a first embodiment of the present invention, FIG. 5 is an enlarged plan view of the main part, FIG. 6 is an enlarged side view of the main part, and FIG. 7 is a perspective view of the main part. 8 and 9 show a second embodiment of the present invention. FIG. 8 is an enlarged plan view of the main part, and FIG. 9 is an enlarged side view of the main part. 1a-ib...Ink, 2...Heater, 3...Ink tank-a.=-.Ink roller. 4a = Ab-4c, a a =----concave = C14e
...Insulating partition. 5...Doctor blade, 6...Paper feed roller, 7...Auxiliary roller. 8... i-9... Head, 9b, 9
c... Discharge pole, 1o... Drive circuit -
104a...Concavity-104e...Insulating partition. 104...... To's part-2042...
Part 4, 204e...Insulating partition part. 209C1209d-209e-209f--=discharge poles. Figure 2 Figure 3 Figure 4 Figure 5 Port 505 Figure 6

Claims (3)

[Claims] (1) A heated ink tank that melts the solid ink, an ink roller with multiple recesses with exposed conductive material that pumps up the molten ink, and a doctor that scrapes off excess ink.
The printer comprises a blade, a discharge nozzle having discharge electrodes, a discharge drive circuit, paper and a paper feed roller, and prints by ejecting ink from the discharge head into the recess. A discharge type non-impact printer characterized in that the concave portions on the ink roller are arranged at intervals so as to correspond to at least every other discharge pole. (2) The discharge type non-impact printer according to claim 1, characterized in that the timing of flowing the current to the discharge electrodes is carried out at a position where one discharge pole does not overlap with the corresponding recess. (3) The discharge-type non-impact printer according to claim 1, characterized in that the discharge electrodes are provided in shifted positions so as not to overlap with the corresponding recesses.