JPS59146863A - Ink jet printer - Google Patents

Abstract

PURPOSE:To obtain the titled printer in which the effect of charged ink particles on one another is alleviated and thereby a multi-value deflection charging control is enabled, by providing a means of giving a movement to an ink particle charged in accordance with a printing information so that it is deflected on a plane perpendicular to the plane of deflection which is formed by a deflection electrode. CONSTITUTION:An ink liquid is pumped from an ink tank 1 by a pump 2 and injected under pressure into the channel of a nozzle 52 of a particle-forming mechanism 5 through a three-way selector valve 3 and a filter 4. Then, ink particles 11 are ejected from a nozzle port 51 toward recording paper 8 by the vibration of a piezoelectric element 53, and the particles 11 thus ejected are charged with electricity by a charging electrode 6 in accordance with printing signals. Thereafter a charged ink particle 12 is deflected by a deflection electrode 7 and collected by a gutter 9, while an ink particle 13 charged with no electricity is made to go straight ahead. Simultaneously, another piezoelectric element 54 is driven to change the form of the nozzle port 51 on a plane perpendicular to the plane of charging deflection in accordance with a frequency. Thereby the ink particles are made to fly along a sine wave within the range of an angle theta and stick onto the recording paper 8 for printing.

Description

DETAILED DESCRIPTION OF THE INVENTION [1] Technical Field The present invention relates to an inkjet printer capable of performing multilevel deflection charge control through a simple assembly.

[2] Prior Art Conventional inkjet printers include, for example, a particle forming mechanism that continuously supplies ink from an ink supply section to a nozzle using a pressure pump and ejects ink particles from the nozzle, and a particle forming mechanism that ejects ink particles from the nozzle. Some inks include a charging pole that charges the particles, and a deflection electrode that causes uncharged ink particles to advance straight and fix them on recording paper, and deflects the charged ink particles and guides them to the gutter.

In the above configuration, the charging of the ink particles by the charging electrode is controlled according to the print signal, the uncharged ink particles are caused to advance straight and fixed on the recording paper, and the charged ink particles are caused to fly and pass through the electrostatic field based on the deflection electrode. By this, the particles are deflected and collected by the gutter, and the D1 constant printing is performed by fixing the particles on the recording paper.

In particular, since the flight trajectory of charged ink particles is affected by the electrostatic repulsion between the particles, a correction voltage is applied to the charging electrode to correct this effect to suppress printing φ caused by the electrostatic and gas repulsion. There is.

However, since conventional inkjet printers apply a corrected frost pressure to the charging electrode, a crudely constructed charge amount control circuit that applies a corrected single pressure becomes necessary, which may increase costs. There is.

[3] Purpose and Structure of the Invention The present invention has been developed in view of the above, and in order to avoid the need for a load %I amount control circuit with a complicated configuration and to suppress an increase in cost, an ink particle deflection electrode is used. The present invention provides an inkjet printer in which the influence of charging between adjacent ink particles is alleviated by giving ink particles a movement of deflecting in a plane perpendicular to a deflection surface.

[4] Examples The inkjet printer according to the present invention will be described in detail below.

1 and 2 show an embodiment of the present invention, in which an ink tank 1 for storing ink liquid, a small pump 2 for pumping the ink liquid from the ink tank 1 to the outside, and a connection to the outlet side of the pump 2. a three-way switching valve 3 for supplying ink liquid at a predetermined pressure to the nozzle portion, and switching the output to the ink tank 1 so as to prevent the ink liquid from dripping from the nozzle when the atomization operation is stopped;
A filter 4 connected to the nozzle side output of the directional control valve 3
, a particle mechanism 5 connected to the output side of the filter 4 to make the ink liquid into particles and eject it in the direction of the recording paper, and a charging electrode 6 to charge the ink particles ejected from the particle mechanism 5 according to the print content. , a deflection electrode 7 that deflects and stirs charged ink particles, a gutter 9 that deflects and collects ink particles that have arrived just in front of the recording paper 8, and filters ink liquid from the gutter 9 and the three-way cutting valve 3. filter 10 and pump 2.3
It is composed of a control section 20 that controls each of the directional switching valve 3, the particle forming mechanism 5, the @city tram, the pole 6, and the deflection electrode 7 via a driver.

The atomization mechanism 5 includes a nozzle 52 having a nozzle port 51 that presses out the ink liquid that is pressurized from the pump 2 via the filter 4, and a vibration that generates particles of the ink liquid that is forced out from the nozzle 52. and a piezoelectric element 54 bonded to the nozzle 52 to give an oscillating motion to the ink droplets so as to deflect the ink droplets in a plane perpendicular to the deflection plane of the ink droplets (FIG. 2). and a support base 55 for fixing the nozzle 52.

The control unit 20 also includes an input interface 21 that inputs various sensor signals, print signals, etc. into the control unit 20 as data, a ROM 22 that stores programs for processing input data, and a ROM 22 that reads data based on the programs in the +ROM 22. a CPU 24 that processes and controls each section;
R that temporarily stores processing results and data of the CPU 24
It is composed of an AM 25 and an output interface 26 that outputs a control signal output based on the processing result of the CPU 24 to a driver (not shown) connected to each part to be controlled.

In the above configuration, when a printing operation is started, the pump 2 is activated and pressurizes the ink liquid into the channel of the nozzle 52 via the three-way switching valve 3 and the filter 4. At the same time, the piezoelectric element 53 is driven at a predetermined frequency by the control unit 20, and a high DC voltage is not applied to the deflection electrode 7. During the charging process, a predetermined pulse voltage of 1 voltage is applied to the electrode 6 according to the print signal. applied. The vibration of the piezoelectric element 53 causes the ink particles 11 to be ejected from the nozzle opening 51 toward the recording paper 8 .

The ejected ink particles 11 are charged by the charging electrode 6 according to the print signal, and the charged ink particles 12 are charged by the deflection electrode 7.
The ink particles 13 are deflected by the ink particles and collected by the gutter 9. On the other hand, the ink particles 13 that have been energized are not deflected and are collected by the gutter 9. At the same time, when the piezoelectric element 54 is driven at a predetermined frequency, the nozzle orifice 51 is deformed in a plane perpendicular to the charging deflection plane according to the frequency, and the ink particles fly away from the frame forming a sin waveform within the range of angle θ. The ink particles 13 that have not been charged through this flying process adhere to the recording paper 8 over a predetermined width W and perform a printing operation.

To explain the above embodiment more specifically, the nozzle 52 is formed by laminating several etched plates, the nozzle opening 51 is 28 μm in diameter, and the ink liquid is introduced into the channel at a rate of 10 m/sea. /Bee ink droplets are releasably formed. Further, the frequency of the piezoelectric element 54 is 08
Set to KH. With this configuration, the print driver]
・When formed with a deflection angle θ, the number of scanning lines is 1.6X10
books/second can be obtained. Near the peak of the deflection angle, there is a risk that the spacing between printed dots becomes high when printing, so the ink particles near the peak are charged and deflected to form the gutter 9.
Make sure to collect it. Note that the distance from the nozzle opening 51 to the recording paper 8 is 10WR, and the interval between the deflection electrodes 70 is 1.6.
When used as a cylinder, a deflection voltage of about 4 KV is required.

FIG. 3 shows an application example of the present invention, and is an example in which the particle forming mechanism 5 shown in FIG.
In a configuration in which the required number of particle forming mechanisms 5 having a configuration in which It is different from the one in Figure 1. Obi tram 1
As the number of poles increases, the number of charged 1% I poles as shown in Figure 4 is increasing.
shall be. The band v4I electrode 40 is a polar tunnel 42.4 through which ink particles 11 ejected from the particle forming mechanism 5 pass.
3.44 is provided, and an electrode body 45 is provided at the periphery of this tunnel.
．． 46 and 47 are formed, and the pulse voltage is applied to the controller 20.
is applied based on the control signal of

When a voltage is applied to the electrode bodies 45 to 47, ink particles passing through the tunnel are charged.

In addition, in the above explanation, an example was shown in which a piezoelectric element is used as an excitation source, but if sufficient mounting space is provided, magnetostrictive vibration
Children can also be used.

[5] Effects of the Invention According to the inkjet printer of the present invention, adjacent ink particles are deflected by giving the ink particles a movement that deflects them in a plane perpendicular to the deflection plane of the ink particles by the deflection electrode. Since the influence of charging between the two is alleviated, a complicated charge resistance control circuit can be omitted, thereby suppressing an increase in cost.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an embodiment of the present invention. Figure 2 is the first
FIG. 3 is a side view of the inkjet unit of the illustrated embodiment. FIG. 3 is a plan view showing an example of application of the present invention. FIG. 4 is a front view of the charging electrode 40 used in the device shown in FIG. 3. Description of right column 5...Particle generator 41gz b, 4o...Charging electrode, 7...Deflection electrode, 9...Gutter, 20
...Control unit, 51...Nozzle CI, 52...Nozzle, 53.54...Piezoelectric element, 55...Support stand.

Claims (1)

[Claims] An inkjet printer that prints by charging and deflecting ink liquid according to print information, characterized in that it is provided with means for imparting a movement to deflecting ink particles in a plane perpendicular to a deflection plane by a deflection electrode.