JPS5981178A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To prevent shortcircuiting from occurring between a recording electrode and a controlling electrode and an overcurrent from being generated due to an abnormal electric discharge, by a method wherein a current-restricting resistor having a specified resistance is provided between a recording electrode and a controlling electrode. CONSTITUTION:A meniscus of a magnetic ink 15 is formed at the tip of the recording electrode 13 magnetized by an ink-raising magnet 18, and a recording paper 17 and the controlling electrode 14 are provided at extremely small interval (about 200mum) from the recording electrode 13. A bias voltage is previously impressed between the recording electrode 13 and the controlling electrode 14 by a power source 23, and voltage pulses of opposite polarities are impressed on the electrodes 13 and 14 respectively by a recording electrode driving part 21 and a controlling electrode driving part 22 when recording an image. A protective resistor 25 having a resistance of 10<6>-10<8>OMEGA for controlling an electric current is provided between the electrodes 13, 14. Accordingly, by providing the protective resistor 25 so as to restrict only the electric current in a circuit connecting the recording electrode 13 to the bias power source and the controlling electrode 14, it is enabled to protect the electrodes 13, 14 and the driving parts 21, 22 from being broken.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an ink jet recording apparatus that jets ink using Coulomb force to obtain a recorded image on recording paper.

Conventional Structures and Problems There is a magnetic ink recording apparatus as an ink jet recording apparatus that obtains recording by ejecting ink using Coulomb force.

A conventional magnetic ink recording device will be explained below.

No. 1- shows a schematic configuration diagram of a conventional magnetic ink.

In the figure, 1 is a recording electrode made of magnetic material, 2 is a control electrode, and 3 is a recording electrode made of a magnetic material.
4 is a magnetic ink, 4 is an auxiliary electrode provided near the recording electrode 1 so as to be in contact with the magnetic ink 3, 5 is a recording paper, and 6 is a magnetized recording electrode 1, and a meniscus of the magnetic ink 3 is formed at the tip thereof. 7 is a control electrode 2;
A platen 8 supports the recording electrode 1, and 8 is a base supporting the recording electrode 1. 9 is a recording electrode drive unit for selectively applying a positive pulse voltage to the recording electrode 1; 1o is a control electrode drive unit for selectively applying a full negative pulse voltage to the control electrode 2; 1;
1 is a bias power supply for applying a recording bias voltage between the recording electrode 1 and the control electrode 2; 12 is an auxiliary electrode power supply for applying a voltage of the same polarity as the pulse voltage applied to the recording electrode 1 to the auxiliary electrode 4; .

The operation of the conventional magnetic ink recording apparatus configured as described above will be described below.

In FIG. 1, a meniscus of magnetic ink 3 is formed at the tip of the recording electrode 1, which is magnetized by the protruding magnet 6. This recording electrode 1 and a very narrow interval (about 200 μm)
After that, a recording paper 5 and a control electrode 2 are provided. Furthermore, voltage pulses of opposite polarity are applied to the recording electrode 1 and the control electrode 2 by a recording electrode drive section 9 and a control electrode drive section 10, respectively, during image recording. A bias voltage is applied to the recording electrode 1 and the control electrode 2 in advance by a bias power supply 11, and a voltage of 1.8 Kv to 2.0 Kv is applied between the recording electrode 1 and the control electrode 2 during recording. A voltage of OKV is applied. The magnetic ink 3 at the tip of the recording electrode 1 flies toward the recording paper 5 due to the Coulomb force caused by the electric field created by this voltage, thereby forming an image. When the magnetic ink 3 is consumed by flying, a coulomb is applied to the tip of the recording electrode 1 due to the force acting on the magnetic ink 3 due to the magnetic force gradient created by the bumping magnet 6 and the electric field created between the auxiliary electrode 4 and the control electrode 2. The power is supplied again and the next recording becomes possible. In addition to the function of supplying the magnetic ink 3 to the recording electrode 1, the auxiliary electrode 4 also has the function of preventing the concentration of the magnetic ink 3 near the tip of the recording electrode 1, and the function of supplying electric charge to the magnetic ink 3. .

However, in the above configuration, the distance between the recording electrode 1 and the control electrode 2 is very narrow, a very high voltage is applied between them, and the recording paper 6 has good air permeability and does not act as an effective insulating material. Even a slight change in the set position of control electrode 1 or control electrode 2 is likely to cause a short circuit. As a result, not only the recording electrode 1 and the control electrode 2 are completely damaged, but also the recording electrode drive unit 9 and control electrode drive unit 10 are damaged, and because the recording voltage cannot be increased, clear recording cannot be achieved. OBJECT OF THE INVENTION The present invention solves the above-mentioned conventional problems, and aims to obtain stable recording with a sufficiently high recording voltage, and to improve recording electrodes,
The object of the present invention is to provide an ink jet recording device that enables protection of control electrodes and circuits.

Structure of the Invention The present invention is characterized in that a 10.degree.
This is an ink jet recording device equipped with a resistor with a resistance value of 6Ω to 108Ω.This resistance prevents short circuits between the recording electrode and control electrode and overcurrent due to abnormal discharge, and prevents overcurrent caused by abnormal discharge between the recording electrode, control electrode, and voltage application circuit. It is possible to protect the

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. Second
The figure shows a schematic configuration diagram of a magnetic ink recording apparatus according to an embodiment of the present invention. In FIG. 2, 13 is a recording electrode made of a magnetic material, 14 is a control electrode, 15 is magnetic ink, and 16 is a recording electrode 1 in contact with the magnetic ink 16.
17 is a recording paper; 18 is a protruding magnet for magnetizing the recording electrode 13 and forming a meniscus of magnetic ink 15 at its tip; 19 is for supporting the control electrode 14; platen, 2o is recording electrode 1
3, 21 is a recording electrode drive unit for selectively applying a full positive pulse voltage to the recording electrode 13, and 22 is a control electrode for selectively applying a negative pulse voltage to the control electrode 14. A drive unit 23 is a bias power supply for applying a recording bias voltage between the recording electrode 13 and the control electrode 14;
4 is an auxiliary electrode power source that applies a voltage of the same polarity as the pulse voltage applied to the recording electrode 13 to the auxiliary electrode 16, and 25 is a protective resistor.

The operation of the magnetic ink recording apparatus of this embodiment configured as described above will be described below.

In FIG. 2, a meniscus of magnetic ink 15 is formed at the tip of the recording electrode 13 magnetized by the bump magnet 18. This recording' electrode 13 and a very narrow interval (200
The recording paper 17 and the control electrode 14 are provided with a distance of about .mu.m) from each other. Furthermore, these recording electrodes 13 and 4i! During image recording, voltage pulses of mutually opposite polarities are applied to the I-ichi pole 14 by a recording electrode drive section 21 and a control electrode drive section 22, respectively. A bias voltage is applied to the recording electrode 13 and the control electrode 14 by a bias power supply 23 in advance. During recording, there is a voltage of 1.8K between the recording electrode 13 and the control electrode 14.
A voltage of V to 2KV is applied. The magnetic ink 15 at the tip of the recording electrode 13 flies along with the recording paper 17 due to the Coulomb force caused by the electric field generated by this voltage, thereby forming an image.

When the magnetic ink 15 is ejected, a force acting on the magnetic ink 15' due to the magnetic force gradient created by the bumping magnet 18 and a force acting on the auxiliary electrode 1
6 and the Coulomb force due to the electric field created between the control electrode 14, and the next recording becomes possible. In addition to the function of supplying the magnetic ink 16 to the recording electrode 13, the auxiliary electrode 16 has the function of preventing the concentration of the magnetic ink 15 near the tip of the recording electrode 13 and the function of supplying charge to the magnetic layer 16. Furthermore, in this embodiment, a protective resistor 26 is provided between the recording electrode 13 and the control electrode 14 to limit the current. This protective resistor 26 has a resistance value of 106Ω to 1o8
Ω, and the magnetic ink 15 flows from the recording electrode 13 to the recording paper 1.
This value is sufficient to cause the current to flow through the circuit when it flies into the air. However, if excessive current attempts to flow due to abnormal discharge or short circuit, the current will be limited.
Recording electrode 13. Control electrode 14. Recording electrode drive section 21. The control electrode drive unit 22 can be protected.

As described above, according to this embodiment, by providing a protective resistor between the recording electrode and the control electrode, the recording electrode, the control electrode,
Not only does it prevent damage to the drive circuit, but it also makes it possible to record at a sufficiently high recording voltage, resulting in a clear image with high density.

Next, another embodiment of the present invention will be described with reference to FIG.

FIG. 3 is a schematic diagram of a magnetic ink recording apparatus according to another embodiment of the present invention.

In FIG. 3, reference numeral 13 denotes a recording electrode made of magnetic material;
4 is a control electrode, 15 is magnetic ink, 16 is magnetic ink 1
6, an auxiliary electrode provided near the recording electrode 14, 17 a recording paper, 18 magnetizing the recording electrode 13;
A protruding magnet for forming a meniscus of the magnetic ink 15 at its tip; 19 a platen for supporting the control electrode 14; 2o a base for supporting the recording electrode 13;
21 is a recording electrode drive unit for selectively applying a positive pulse voltage to the recording electrode 13; 22 is a control electrode drive unit for selectively applying a negative pulse voltage to the control electrode 14; 23 is an Iasumi source (for applying a recording bias voltage between the recording electrode 13 and the control electrode 14); 24 is an auxiliary electrode power source that applies a voltage of the same polarity as the pulse voltage applied to the recording electrode 13 to the auxiliary electrode 16; The structure is the same as that shown in Fig. 2.The difference from the first embodiment is that the protective resistor 26 is placed on the positive side of the bias power supply 23 and on the auxiliary electrode power supply 24 as shown in Fig. 3. Negative electrode side and recording electrode drive section 21
This is the point set between.

The operation of the magnetic ink recording apparatus of the second embodiment configured as described above will be explained.

The operation of the second embodiment shown in FIG. 3 is substantially the same as the first embodiment shown in FIG. The difference is that in FIG. 3, a protective resistor 26 is provided on the positive side of the bias power source 23 and between the negative side of the auxiliary electrode power source 24 and the recording electrode drive unit 21. Since abnormal discharge or short circuit occurs between the recording electrode 13 and the control electrode 14 during recording, as shown in FIG. Recording electrode drive section 21. Bias power supply 23. It is believed that it is best to provide a protective resistor so as to limit only the current in the circuit connecting the control electrode drive section 22 and the control electrode 14. Furthermore, since the protective electrode 26 is provided in this way, the voltage applied between the auxiliary electrode 16 and the control electrode 14 will not drop even if the magnetic ink 15 flies onto the recording paper 17 and current flows through the circuit. First, the magnetic ink 15 can be efficiently supplied to the tip of the recording electrode 13 and the charge can be supplied efficiently.

As described above, according to this embodiment, by providing the protective resistor so as to limit only the current of the circuit connecting the recording electrode, the bias power supply, and the control electrode, the recording electrode, the control electrode, the recording electrode drive unit, In addition to protecting the control electrode drive unit from damage, the auxiliary electrode bias power supply and the current of the circuit connecting the control electrodes are not limited, so the ability to supply one-meter ink to the tip of the recording electrode by the auxiliary electrode, and the magnetic Does not inhibit charge supply to the ink. Therefore, a clearer image with higher density can be obtained. Although the protective resistor 25 is provided on the positive electrode side of the bias power source 23 in the above embodiment, it is not implied that it may be provided on the negative electrode side of the bias power source 23.

Effects of the Invention As described above, according to the ink jet recording device of the present invention, the recording electrode, the control electrode, and the drive section can be protected by providing a protective resistor for current limitation between the recording electrode and the control electrode. Since it is possible to perform recording at a sufficiently high recording voltage, it is possible to stably obtain high-quality printing.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a conventional magnetic ink recording device;
FIG. 3 is a schematic diagram of a magnetic ink recording apparatus according to an embodiment of the present invention, and FIG. 3 is a schematic diagram of a magnetic ink recording apparatus according to another embodiment of the present invention. 1... Recording electrode, 2... Control electrode, 3
...Magnetic ink, 4...Auxiliary electrode, 6
...Recording paper, 6...Elevation magnet, 7.
...Platen, 8...Base, 9...
... Record 7 "Pole drive unit, 10... Control electrode drive unit, 11... Bias power supply, 12...
Auxiliary electrode power supply, 13... Recording electrode, 14...
...Control electrode, 16...Magnetic ink, 16.
...Auxiliary electrode, 17...Recording paper, 1 day.
...Magnet for elevation, 19...Platen, 2
0... Base, 21... Recording electrode drive unit, 22... Control electrode drive unit, 23...
Bias power supply, 24...Auxiliary electrode power supply, 25.
...Protection resistance, 26...Protection resistance O

Claims (2)

[Claims] (1) A recording voltage is selectively applied to a plurality of nozzles or recording electrodes, a control electrode that faces the plurality of nozzles or recording electrodes with a recording paper in between, and the nozzles or recording electrodes and the control electrode, respectively. bias voltage applying means for applying a bias voltage between the nozzle or recording electrode and the control electrode;
An ink jet recording device equipped with a resistance member having a resistance value of 0.08Ω. (2) A recording voltage is selectively applied to a plurality of nozzles or recording electrodes, a control electrode facing the plurality of nozzles or recording electrodes with a recording paper in between, and the nozzles or recording electrodes and the control electrode, respectively. bias voltage applying means for applying a bias voltage between the nozzle or recording electrode and the control electrode;
a resistance member having a resistance value of 0.08Ω, an auxiliary electrode provided near the nozzle or recording electrode so as to be in contact with the ink, and an auxiliary voltage application for applying a voltage between the auxiliary electrode and the nozzle or recording electrode. An ink jet recording device comprising means.