JPS5991068A - Correcting method of multi nozzle ink jet recording distortion - Google Patents

Abstract

PURPOSE:To make the correction possible so that good recording can be obtained even though the times of simultaneously charged ink particles required for reaching a recording paper are different, by changing charge voltage, that is, deflection amount to each of nozzles. CONSTITUTION:Plural pieces of jets are divided into lines of ink particles 3-1, 3-2,... synchronized with a basic clock by a method wherein signals from basic clock generator 9 is sent to an oscillating amplifier 10 and oscillates a vibrator 2. After signals from a recording signal generator 13 is stored in a print buffer 14 for a time, it is sent to an amplifier for correction of charge 12 according to the signal from basic clock generator 9, settles the charge voltage to respective jets according to the data of recorder 11 such as ROM and the like at the amplifier 12, and sends it to an air resistance and electrostatic repulsion strain correction circuit 15. The voltage settled at the amplifier 12 is superimposed with the correcting voltage from a correction circuit 15, and sent to charge electrodes 4-1, 4-2,... as the last charge voltage. That is, the recording distortion due to the flow difference of respective nozzles and the difference of disconnection, can be restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention corrects recording distortion caused by manufacturing errors of individual nozzles in a quantity-controlled multi-nozzle inkjet.
The present invention relates to a multi-nozzle inkjet recording distortion correction method for obtaining good recording quality.

The multi-nozzle inkjet system that controls the amount of electric charge, as shown in the principle diagram of FIG. Cut into regular rows of ink particles 3.

The ink particles 3 used for recording are charged with a charge of 1! corresponding to each nozzle 10 when the particles are cut. A charge is given by the pole 4. The charged ink particles 3 are deflected by passing between two deflection electrodes 50 forming an electric field, and recorded on the recording paper 8. On the other hand, particles that cannot be used for one needle move forward into the gutter 6.
1 will be collected. Note that 7 is an ink supply pipe.

Regarding the operation of conventional multi-nozzle inkjet, 1.
This will be explained with reference to Figure iB2. In Figure 2, (a) to (
c) shows various states of the ink particles 30, each (1) shows the particle state, (II) shows a recording example 1, B shows the recording paper moving direction, that is, the sub-scanning direction, and C shows the ink particles 3
is the direction of flight. Further, 3' indicates an ink column. Second
As shown in Figure (a) K, the first jet is cut at the same position, and after cutting, the ink droplet 3 is ejected from which nozzle 1 and flies at the same speed. t
It was set as l. Therefore, in order to record in a straight line as shown in (11) in Figure 2 (a), it is considered that all nozzles 1 should be charged at the same time with the same voltage. Only the electrostatic repulsion between particles was corrected.

However, it is actually difficult to manufacture such a highly accurate nozzle 1, and generally, as shown in Fig. 2(b), the cutting distance of each nozzle 1 may vary due to manufacturing errors of each nozzle 1. different. Therefore, even if the ink particles 3 are charged with the same pressure at the same time, there will be a difference in the time they take to reach the recording paper 8 depending on the nozzle 1. On the other hand, since the recording paper 8 is moving relatively in the sub-scanning direction B, which is substantially perpendicular to the flight direction CVc of the ink particles 3, the difference in arrival time directly appears as recording distortion. The same applies when the speeds of the ink particles 3 are different as shown in FIG. 2(C).

These first and other recording distortions are different from those caused by conventional air resistance or electrostatic repulsion, and are caused by differences between the individual nozzles 1, and therefore cannot be eliminated by conventional methods alone.

In order to solve the first and other drawbacks, the present invention changes the charged lightning, pressure, or deflection area for each nozzle, so that the ink particles that are charged at the same time can reach the recording paper at different times. The feature is that the iC record is corrected in the first to fifth order. A detailed explanation of this invention will be given below with reference to the drawings.

FIG. 3 is a diagram showing an embodiment of the present invention.

In this figure, 9 is a basic clock generator, 10 is an excitation amplifier, 11 is a dC storage box, 12 is a 7-electrode for charge correction, 13 is a recording (FT signal generator, 14 is a print buffer, and 15 is an air resistance - An electrostatic repulsion distortion correction circuit is shown.In an actual device, a circuit for determining the charge phase is required in addition to this, but it is omitted because it is not directly related to this invention.

Next, the operation will be explained. The signal from the basic clock generator 9 is not sent to the vibrator 7 10, and by vibrating the vibrator 2, a plurality of jets are generated in a row of ink droplets 3-1, 3-2, 3-2, 3-1, 3-2, 3-2, 3-2, 3-2, 3-2, 3-2, 3-2, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 the signal from the basic clock generator 9 is not sent from the basic clock generator 9. ...It is divided into nine parts.

The signal from the recording signal generator 13 is temporarily stored in the print buffer 14, and then the basic clock is generated 'r:::9
Jl, which is sent to the charge correction amplifier 12 according to the signal from Jl,
In the charge correction section 12, set the charge 117.1 UL pressure for each jet according to the data in the ROM etc. The correction voltage from the air resistance/electrostatic repulsion distortion correction circuit 15 is superimposed on the voltage set by the charge correction amplifier 12, and the final charge ′r[j pressure is calculated as the charge electrode voltage. Cannot send to 4-1.4-2.

As a method of setting the charging voltage in the charging correction amplifier 12, there is a method as shown in FIG. 4(a) Ab), for example. Here, 16-1 is the trajectory of the ink droplet 5 of the ink droplet 3 used for recording that is ejected from the nozzle 1 with a faster speed, and 16-2 is the ink droplet that is ejected from the nozzle 1 with a slower speed of the ink droplet 3 used for recording. Particle trajectory 16-3 indicates the trajectory of the first ink particle that is not used for recording and is collected in the gutter 6. Also, 8
is the same as that shown on recording paper C, FIG. The data in the tte storage device 11 is actually recorded and created from seven distortions.

Figure 4(a) shows the case where nine charged particles are used,
By deflecting the slow ink droplets (trajectory 16-2) greatly in the paper feed direction BK, even if the arrival time is different, the relative movement of the recording paper 8 to the ink droplets 3 during that time can be eliminated, and recording distortion can be avoided. does not occur. Also, the fourth
Figure (b) basically shows the case where uncharged particles of trajectory 16-1 are used for recording, and this trajectory 16-1 has a slower velocity than the first trajectory.
-2 ink particles 3 are deflected in the paper feeding direction BK. In addition, ink droplets 73 that are not used for recording are deflected in the opposite direction (trajectory 16-32°).In addition to this, various methods of deflection can be considered.For example, if the paper feeding direction B is reversed and Tl1 is -2
The ink droplet 3 becomes the faster ink droplet, and the trajectory 1
Ink particle 3 of 6-1 is a slow ink particle VC-f
A similar effect can be obtained by Kototakumi.

As explained above, according to the present invention, it is possible to suppress recording distortion due to differences in flow velocity between individual nozzles and differences in cutting distance, which not only improves recording quality but also enables use with multiple nozzles with low precision. Convenient nJ'fi'Q IC
Therefore, the nozzle 7 is also advantageous in terms of manufacturing yield.

[Brief explanation of drawings]

Figure 1 shows the principle of multi-nozzle inkjet 11g+,
Figures 2 (a) to (c) are diagrams showing the particle state and recording examples; (a) is when there is no AL recording distortion, (b) is when there is recording distortion due to a difference in cutting distance, ( e) is a case of recording distortion due to different ink particle flight speeds, FIG. 3 is a block diagram showing an embodiment of the present invention, and FIGS. 4(a) and (b).
) is a diagram showing an example of ink droplet deflection when the present invention is used. In the figure, 1 is a nozzle, 2 is a vibrator, 3 is an ink particle, 4 is a load 1u electrode, 5 is a supine electrode, 6 is a gutter, 1 is an ink common supply tube, 8 is a recording paper, 9 is a basic clock generator 10 is an excitation amplifier, 11 is a storage device, 12 is a charge correction amplifier, 13 is a recording signal generator, 14 is a print buffer, 1
5 is an air resistance/electrostatic repulsion distortion correction circuit, 16-1 to 16-
:( is the trajectory of ink particles.

Claims (1)

[Claims] In a charge amount control type inkjet system having a plurality of nozzles, the charging voltage is corrected according to the difference between individual nozzles in the time it takes for ink particles to reach the NIJ recording paper from the first time a charging signal is applied. A multi-nozzle inkjet recording distortion correction method characterized by eliminating recording distortion by changing the deflection group of ink particles for each nozzle.