JPS604065A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain steady recording by surely charging small size particle, by a method wherein the generating zone of small size particle is detected in a broad range and the phase adjustment of separation timing of small size particle and of charge signal to small size particle is accurately carried out. CONSTITUTION:When the amplitude of exciting voltage (e) of high frequency power source 3 is changed, the generating mode of ink particle and the length lP of ink column 9 are changed. When the exciting voltage (e) is increased, the length lP of ink column 9 is shortened and the generation mode of ink particle is changed (a)-(d). The separation of small size particle 10 from ink column 9 i synchronized with the frequency of excitation voltage (e) of piezoelectric element 4 and the phase theta of its separation timing is changed by excitation voltage (e) and can be regulated within a range of 0-2pi in this excitation frequency. Thereby, the excitation voltage is regulated and the excitation intensity to the ink injected from nozzle is regulated. Therefore, by sure generation of small size particle 10 and by the sure conformance of information signal and separation timing from small size particle 10, steady sure recording by small size particle can be carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an in-jet recording device, and particularly to an inkjet recording device that performs recording using at least small-diameter ink particles among two types of ink particles ejected from a nozzle. -Relates to inkjet recording devices.

[Background of the invention]

In inkjet recording, pressurized ink is supplied to a nozzle, and this nozzle is excited by an electrostrictive vibrator excited by a high-frequency power source, and the ink is ejected from the nozzle hole to create ink particles. particles,
Ink particles are charged according to the information signal, passed through a constant electric field, and deflected according to the amount of charge the ink particles have to obtain a specified record on the recording medium (generally called charge modulation type). ) is publicly known.

This charge modulation type inkjet recording device alternately produces ink particles of large diameter and small diameter from the nozzle hole by appropriately setting ink droplet formation conditions such as ink supply pressure, nozzle excitation intensity, and excitation frequency. can be generated.

Therefore, we have previously proposed an inkjet recording device that uses the small-diameter ink particles (hereinafter simply referred to as small-diameter particles) for recording by giving them an electric charge according to an information signal from an information signal source (particularly (No. 33519, 1973).

According to this method, it is possible to generate small-diameter particles (with a diameter of about 173 mm compared to the large-diameter particles) from a relatively large nozzle hole, so the nozzle hole is easy to manufacture, and the nozzle rim is easy to manufacture. Since the number of particles is small, reliability is improved, and since recording can be performed using small-diameter particles, it has the advantage that high recording density and high quality images can be recorded.

However, on the other hand, it stabilizes small diameter particles from the nozzle.

The above advantages cannot be achieved unless the separation timing of the small-diameter particles and the phase of the information signal match.

However, due to changes in ambient temperature, humidity, physical properties of ink, etc., it has become difficult to generate small-sized particles stably, and the phase matching between the separation timing of small-sized particles and the information signal may not be performed properly. be.

Therefore, we first proposed an inkjet recording device that automatically performs this correction (Japanese Patent Laid-Open No. 56-126i73i
) However, this method does not allow correction over a wide range and cannot always be properly corrected, so it requires some manual operation, and it is not yet reliable.

[Purpose of the invention]

The present invention automatically detects the generation area of small-diameter particles over a wide range, and furthermore, quickly and accurately performs the separation timing of small-diameter particles and the phase matching of the charge signal to the small-diameter particles. The object of the present invention is to provide an inkjet recording device that can reliably charge particles and obtain stable recording.

[Summary of the invention]

The configuration of the inkjet recording device according to the present invention is to eject pressurized ink through a nozzle, and by adjusting the excitation intensity to the nozzle, to alternately and stably generate large-diameter and -small-diameter ink particles, and to generate at least small-diameter ink particles. In an inkjet recording apparatus that reliably charges ink particles with a recording signal, the means for adjusting the excitation intensity includes a first excitation adjustment means for coarsely adjusting the excitation, and an excitation adjustment range within the excitation adjustment range by the first excitation adjustment means. A second excitation adjustment means for finely adjusting the excitation intensity, and a third excitation adjustment means for finely adjusting the excitation adjustment range by the second excitation adjustment means, and each of these adjustment means is sequentially operated to adjust the excitation intensity. It is configured to be set to a predetermined value.

As an additional note, the present invention is directed to large,
In an inkjet recording device in which a small diameter particle among two types of small ink particles is charged according to an information signal and deflection controlled to obtain a desired recorded image on a recording medium, the intensity of excitation is roughly adjusted. The first excitation adjustment means detects a wide area where small-diameter particles are generated, and the second excitation adjustment means finely adjusts the range of excitation adjustment by the first excitation adjustment means, and the timing of separating the small-diameter particles and the charging of the small-diameter particles are adjusted. A third excitation adjustment means detects at high speed an appropriate region where the phase of the signal matches, and further finely adjusts the excitation adjustment range within the excitation adjustment range by the second excitation adjustment means, and adjusts the excitation intensity to an optimal point within the appropriate region. It was designed to be adjusted.

[Embodiments of the invention]

Each embodiment of the present invention will be described based on the drawings.

First, FIG. 1 is a schematic enlarged sectional view of a nozzle part that constitutes a part of an inkjet recording apparatus according to an embodiment of the present invention, and FIG. 2 shows an excitation voltage applied to a piezoelectric element of the nozzle part. FIG. 3 is a characteristic diagram showing the relationship between the excitation voltage and the length of the ink column of the nozzle.

In other words, in FIG. 1, pressurized ink 2 is supplied from an ink tank to a nozzle 1, and is excited by a high frequency power source 3 around the outer periphery of this nozzle 1, and the nozzle l
A piezoelectric element 4 is attached to vibrate the ink 2 inside.

The nozzle 1 is composed of a metal pipe 5 and an oriswiss plate 7 having a nozzle hole 6 for ejecting the ink 2. When a high frequency voltage is applied from the nozzle 3, the ink 2 in the nozzle 1 is ejected through the nozzle hole 6 as an ink column 9, and is separated into small-diameter particles 10 and large-diameter particles 11.

When the output voltage of the high frequency power supply 3, that is, the amplitude of the excitation voltage e is changed, the ink droplet generation mode and the length tp of the ink column 9 change as shown in FIGS. 2 and 3. do.

, FIG. 2 shows that the ink particle generation mode and the excitation voltage e
Explain the relationship between

When the excitation voltage is small, as shown in mode a, the flight speed of the small particles 10 is slower than the speed of the large particles 11, and the small particles 10 are caught up with the large particles 11 during flight and coalesce. Next, when the amplitude of the excitation voltage e is slightly increased, as shown in mode b, the speeds of the small diameter particles 10 and the large diameter particles 11 become almost equal, and the small diameter particles 10 and the large-diameter particle 11 fly forever without coalescing. This state is called medium speed mode.

Furthermore, when the amplitude of the excitation voltage e is increased, ink droplets are generated in mode C. In this state, the speed of the small-diameter particles 10 is faster than the speed of the large-diameter particles 11, and the small-diameter particles 10 catch up with the large-diameter particles 11 and coalesce. This state is called high speed mode.

When the amplitude of the excitation voltage e is further increased, the small diameter particles 10 are not generated at all and only the large diameter particles 11 are generated, as shown in '-d'. This state is called a small diameter no mode.

FIG. 3 shows such excitation voltage e and the length t of the ink column 9.
, and the ink droplet generation mode. When the excitation voltage e is increased, the length tp of the ink column 9 is shortened, and the ink droplet generation mode changes from a to d.

This is because when the total excitation voltage increases, the excitation intensity to the ink ejected from the nozzle 1 increases, and the ink column 9
As the initial vibration that occurs in the ink column 9 becomes larger, the amplitude of the periodic constriction that occurs in the ink column 9 is accelerated, and as a result, the ink 2 is ejected from the nozzle hole 6, and the ink column 9 finally separates into ink particles. This will shorten the time it takes to do so.

On the other hand, the separation of the small diameter particles 10 from the ink column 9 is synchronized with the frequency of the excitation voltage e of the piezoelectric element 4 excited by the high frequency power source 3, and the phase θ of the separation timing changes depending on the excitation voltage e. This excitation period can be adjusted within the range of 0 to 2π.

From the above, by adjusting the excitation voltage and the excitation intensity to the ink ejected from the nozzle l, it is possible to reliably generate small diameter particles 10 and to control the separation timing between the information signal and the small diameter particles 10. It was found that by ensuring a reliable match, stable and reliable recording using small-diameter particles becomes possible.

Therefore, in the present invention, from the nozzle to the dog,
It is detected that a pair of small ink particles are reliably generated, and then the excitation voltage of the piezoelectric element is set to an excitation intensity that is in the generation area of small diameter particles for the generation of these ink particles. , set the excitation voltage of the piezoelectric element to an excitation intensity in a region where the generation of small-diameter particles and the phase of the information signal match, and further set the excitation voltage of the piezoelectric element to the excitation intensity in the region where the generation of small-diameter particles and the phase of the information signal match. The excitation voltage is set to an excitation intensity that ensures that small-diameter particles are charged.

Next, FIG. 4A is a block diagram of an inkjet recording apparatus according to an embodiment of the present invention, and FIG. 4B is a connection circuit diagram thereof.

In the figure, 12 is a charged deflection electrode, 13 is a gutter, 14 is a detector, 15 is a video amplifier, 16 is an information signal source, 17 is an excitation signal generator, 18 is a waveform shaping circuit, 19 is a control device, 20a, 20b is a digital binary data signal generator, 21a.

21b is a D/A converter, 22 is an adder, 23 is a multiplier,
24 is an excitation amplifier, 25 is a signal processing circuit, 26 is a first excitation voltage adjustment means, 27 is a second excitation voltage adjustment means, and 28 is a second excitation voltage adjustment means.

According to this embodiment, the means for adjusting the excitation intensity includes an excitation signal generating device that generates an excitation signal;
a digital binary data signal generator for generating a digital binary data signal that determines the excitation intensity;
Receiving the same data of the digital binary data signal, two types of sizes A and B (A=A1.A2, AI
)A2>B) A D/A converter that converts into an analog data signal, an adder that adds these two types of analog data signals, and the analog data signal output of this adder and the a synthesizer that receives the excitation signal as an input signal and changes the intensity of the excitation signal output according to the magnitude of the analog data signal; and a first excitation voltage adjustment means that coarsely adjusts the excitation voltage; The second excitation voltage adjustment means for finely adjusting the voltage is set to generate an analog data signal of magnitude A from the D/A converter for the same digital binary data signal X,
The digital binary data signal generator operates as a means for coarsely changing the digital binary data and as a means for finely changing the data, and a third excitation voltage adjusting means for finely adjusting the excitation voltage is
For the binary data signal X, the D/A converter is set to generate an analog data signal B whose thickness is smaller than A, and the binary data signal generator It is configured to operate as a means for changing data more finely.

That is, first, the nozzle 1 is excited by the output signal of the excitation amplifier 24.

In this case, the excitation intensity is determined by, for example, a sine wave of a constant frequency and voltage level output from the excitation signal generator 17 related to a sine wave oscillator, and an analog data signal output from the D/A converters 21a and 21b. Adder 22
This value is determined by adding the signal output from the adder by multiplying the output signal from the adder by multiplying it by 6 by multiplying it by 6.

The above D/A converters 21a and 21b have 8 pins! When a digital binary data signal X (1 or 0) is fully input to this 8-bit input line terminal, an analog data signal corresponding to the input signal is taken out.

For example, when the 8-bit input signals are all 0, the output signal is such that when the Ov1 human input signal is all 1, the output signal is 1V.

Further, in the adder 22, addition coefficients for the output signal of the D/A converter 21a and the output signal of the D/A converter 21b are set separately.

For example, the output signal of the D/A converter 21H is from Ov to 1V.
When the voltage changes from OV to 1v, the output of the adder 22 changes from OV to 1v.
When the output signal of the D/A converter 21b changes from Ov to 1V, the output of the adder 22 changes from OV by 0.2V.

In this way, the value of the output signal of the multiplier 23 can be changed by the inputs of the D/A converters 21a and 21b, so the multiplier 23, the adder 22, the D/A converter 21a,
21b constitutes a programmable gain control amplifier.

Digital binary data signal generator 20a.

20b is provided within the control device 19.

1) The inputs of the /A converters 21a and 21b are connected to the control device 19.
This control device 1 is now controlled by
9, as shown in Figure 4 (b), the central processing unit (
CPU), read-only memory (OM), random access memory (RAM).

Control section (C-
D), a peripheral interface adapter (hereinafter simply referred to as PIA), and a digital binary
The digital binary data signal generator 20a and 20b are configured as data signal output latch elements. Control unit C-D P IAI, P IA2
d, control line C-L, address bus A-B
, are interconnected by a data bus D-B, and P I
Output a predetermined digital binary data signal from the output lines (PB7 to PBo) of Ar through the digital binary data signal generator 20a or 20b to control the inputs of the D/A converters 21a and 21b. It is something. At this time, two D/A converters 21a,
21b is selected and switched using the PIAI output line (PA+
, PAo).

Here, the first excitation voltage adjustment means 26 related to the first excitation adjustment means that roughly adjusts the excitation voltage is connected to the D/A converter 21.
a, and a digital binary data signal generator 20a.
The output line of the upper 4 bits of PIAl (P B
7 to PB4), and converts it into an analog data signal A as shown in the figure and outputs it (Al in this case). The second excitation voltage adjustment means is a D/A converter 21
8-bit output line of PIAt (, PB7)
~PBo), which similarly converts into an analog data signal A and outputs it (A2 in this case),
Further, the third excitation voltage adjustment means 28, which is a third excitation adjustment means for extremely finely adjusting the excitation voltage, connects the D/A converter 21b and the 8-bit output line (PB7) of the PIAt.
~PBo), and converts it into an analog data signal B and outputs it as shown in the figure.
>A2>B. Note that X and X in the figure are digital binaries of the same data! This shows the Jf-ta signal.

Further, the detector 14 is a detector for detecting the amount of charge on the ink particles, and as the ink passes through the detector 14, a signal is induced by the charge possessed by the ink particles.
Detected as a detection signal.

The output signal of this detector 14 is input to a signal processing circuit 25, and is converted into an output signal of a predetermined magnitude by an operational amplifier IC and a comparator ICs.
The signal is input to the Al input line (PA7), and the presence or absence of the signal is determined.

Furthermore, the output of the excitation signal generator 17 is: 1 Schmitt circuit IC6, multivibrator IC? The sine wave high-frequency voltage is input to a waveform shaping circuit 18 consisting of a digital signal generator 18, which converts the sinusoidal high frequency voltage into a digital on/off signal, and inputs the signal to an information signal source 16 and a control device 19.

Therefore, the information signal source 16 is the logic element ICa
, ICs , IC+o and operational amplifier I Co .

1) IA of the control device 19
By applying the output signals of the second output lines (FAI, PAo) to the logic elements IC9 and ICto, a predetermined information signal is output.

The output of this information signal source 16 is amplified to a predetermined voltage by a video amplifier 15 and applied to the charged deflection electrode 12.

In this embodiment having the above configuration, first, the process of detecting the generation of ink particles is performed as shown in FIGS. 5 and 6.
This will be explained with the help of a diagram.

Here, FIG. 5 is a flowchart for detecting the generation of small diameter particles, and FIG. 6 is a diagram of signal waveforms at various parts during the operation.

However, the conditions at this time are that the diameter of the nozzle hole 6 is 60 mm.
μ, excitation frequency 124KH2, ink pressure 1'OKf
/ca, excitation voltage range is 30VpP at °“10”, FO
``'' is set to 150 Vpp.

Here, the excitation voltage is expressed as a hexadecimal number, that is, II I Q
II , N 2Q 11 , , , II 9
Q II, +1 A O”.

° “B O”,... II p Q II.

First, using the first excitation voltage adjusting means 26, as shown in FIG. 5-6, the excitation voltage (a) is set to "'10", and a negative charge detection signal (b) is generated.

Here, the pulse width t of the charge detection signal (b) is set to t=100T, where T is the period of the excitation voltage (a).

However, in this case, the excitation intensity is weak, and the large-diameter particles 11 and small-diameter particles 10 are turned into particles at the tip of the charged deflection electrode 12, so even if they are positively charged, they are not deflected and the detector No signal is generated from 14.

Here, it is determined whether or not the particles have passed through the small-diameter particle generation region, which will be described later. If they have not passed, the process goes to the next step, where the excitation voltage is increased by "10" and the voltage is increased by 20.
+, the charge detection signal (b) can be generated again.

At this time, the large diameter particles 11 and the small diameter particles 10 are charged,
Only the small diameter particles 10 are directed towards the detector 14, as shown in (C) in Fig. 6.
Outputs the signal shown in . Here, the reason why only the small diameter particles 10 go to the detector 14 is that the deflection sensitivity is such that the large diameter particles 11
: Because of the ratio of small diameter particles 10 = 1:9, large diameter particles 11
This is because even if it is charged, it cannot be completely deflected and is collected by the gutter 13.

Further, the time delay Tt of the signal related to the output of the detector 14 shown in FIG. When the distance between the point to be visualized and the detector 14 is set to 40 mrR, T t = l m s.

When there is a charge detection signal as described above, it is ultimately determined whether the excitation voltage II FO++ is present, and if it is not, the ``i o'' continues to increase again in the above manner, and the excitation voltage ``FO'' ”, this process ends.

On the other hand, when the excitation intensity is strong, small-diameter particles 10 are no longer generated, so there is no charge detection signal.

This confirms that the small-diameter particle generation region has been passed, sets the excitation voltage to the boundary '10', and ends this process.

In this way, when the excitation voltage (a) is increased, the small diameter particles 10 disappear and only the large diameter particles 11 are generated. The excitation voltage (a) shown in Fig. 6 is ++ 901
When the value is +, this state is indicated, and the detector 14 outputs no signal.

Figure 7 shows the relationship between the excitation voltage e and the detector output e c++t.
You can check the occurrence area.

In this case, the excitation voltage e is set to '90'' and the next process begins.However, even if the excitation voltage e is set to 'FO', if small diameter particles 10 are confirmed by the detector 14, the above As described above, the excitation voltage is set to "FO" and the next process begins. First, the process of detecting the area where only the small diameter particles 10 can be appropriately charged is performed as shown in FIGS. 8 and 9. This will be explained with the help of a diagram.

FIG. 8 is a flowchart for detecting a phase appropriate region, and FIG. 9 is a diagram of signal waveforms at various parts during the operation.

Here, the reason why only the small-diameter particles 10 are charged is because if the large-diameter particles are also charged, recording distortion and other undesirable results will occur.

Here, using the second excitation voltage adjustment means 27, first, the excitation voltage set by pre-processing (detection of small diameter particle generation area) is decreased by 'O1'', and the force phase is adjusted as shown in FIG. 9(b). A detection signal is output from the video amplifier 15.

A signal is then output from the detector 14 only when the small diameter particles 10 are charged and deflected.

Next, it is determined whether there is a charge detection signal, and if there is a charge detection signal, the excitation voltage is decreased by ``01'' again, and this process is repeated.

If not, it is determined whether or not the proper area has been passed, and if the area has not passed 9, the above-mentioned operation is repeated.

When it is confirmed that υ has passed, change the excitation voltage to the boundary point -
° Set to “3” and end this process.

Here, the excitation voltage "8F" shown in FIG. 9(a) indicates that the excitation voltage e in FIG. 7 is set to 1190 ++ and is related to the processing of -'01".
' further indicates something related to the processing of -II OI ++. Moreover, "' 7 E" indicates the excitation voltage when passing through the appropriate region in FIG. Furthermore, setting the boundary point to -tl 31+ means:
This means that the excitation voltage is further reduced by 3''.

Figure 10 shows the relationship between the excitation voltage e and the detector output e cut, and when the excitation voltage is changed in this way,
Several regions are detected, but under the above conditions, the second region from the one with the highest excitation voltage °゛85''~''
81” is better; in this case, the excitation voltage e*LI
7 ET' and ends this process.

The amount of change in the excitation voltage e at this time is ' o i '', which is 0
．． It was 5Vpp.

Next, the process of setting an excitation voltage e that appropriately charges only small-diameter particles will be explained using FIGS. 11 and 12.

FIG. 11 is a flowchart for setting the appropriate excitation voltage, and FIG. 12 is a diagram of signal waveforms at various parts during the operation.

In this case, the above-mentioned third oscillating voltage adjustment means 28 is used, so that even if the excitation voltage e'f: 01 is increased, the amount of increase is small even in the pre-processing, and the appropriate region can be finely adjusted. It is set to .

Figure 13 shows the relationship between the excitation voltage e and the detector output e cut, and the lower limit of the appropriate range of the excitation voltage e is "O
When F'' and the upper limit is 23″', 23+OF −+ OF=1 9 , and p is set to “19”, and this processing is completed.

At this time, the amount of change in the excitation voltage e is ' 01 ', which is 0, l
It was Vpp.

As a result of the above, only the small-diameter particles 10 can be appropriately charged.

Next, FIG. 14A is a block diagram of an inkjet recording apparatus according to another embodiment of the present invention, and FIG. 14B is a schematic connection circuit diagram thereof.

In the figure, the same reference numerals as in FIG. 4 indicate the same parts, and 19-1 is a control device, and 20a.

20b and 20c are digital binary data signal generators, and 21-1 is a D/A converter.

and a binary data signal generator 20a.

20b and 20c are provided within the control device 19-1.

According to this embodiment, the means for adjusting the excitation intensity includes an excitation signal generating device that generates an excitation signal;
a digital binary data signal generator for generating a digital binary data signal that determines the excitation intensity;
A D/A converter converts the digital binary data signal into an analog data signal, and a D/A converter receives the excitation signal and the analog data signal as input signals and converts the intensity of the excitation signal output depending on the magnitude of the analog data signal. It consists of a synthesizer that changes the digital binary
The data signal generator includes a first excitation voltage adjustment means that coarsely changes the digital binary data, and finely changes the digital binary data within the range in which the digital binary data is changed by the first excitation voltage adjustment means. a second excitation voltage adjustment means for changing the digital binary data; and a third excitation voltage adjustment means for changing the digital binary data more finely within the range in which the digital binary data is changed by the second excitation voltage adjustment means. It is designed to form a .

That is, as shown in the figure, this embodiment includes one D/A converter 21-1 and three digital binary take signal generators 20a.

By configuring 20b and 20c, the first excitation voltage adjustment means, the second excitation voltage adjustment means, and the third excitation voltage adjustment means are constituted similarly to the previous embodiment, and adjustment can be performed in the same manner. It was made so that it could be done.

Therefore, in the illustrated configuration, the I)/A converter 21-1 uses an input line terminal (D++-Do) composed of 12-bit elements, and is connected to a digital binary data signal generator. 20a, 20b, 2
0C is a 4-bit output line (PB7~PB4
), 8-bit output lines (PB7 to PBo), and 8-bit output lines (PB3 to PBo).

(PA3~PAo) and the D/A
The converter 21-1 is composed of logic elements connected to the converter 21-1.

That is, in the first excitation voltage adjustment means, the upper 4 bits of the output line (PB7 to PB4) of the PIAs, the upper 4 bits of the input line terminal of the kD/A converter 21-1 (Do-D
s) is connected, and the other inputs of the D/A converter 21-1 are held at 0. Next, the area where small-diameter particles are generated is detected by adding a small-diameter particle detection signal while increasing the digital binary data signal of the upper 4 bits of the PIAI (PB7 to PB4) one by one. be.

In addition, the second excitation voltage adjustment means connects the 8-bit output line (PB7 to PBo) of PIA+ to the D/A converter 2.
1-1 upper 8-bit input terminal (D++~D4
) may also be connected to the first excitation voltage adjusting means, but only the upper 4 bits are operated. ), the digital binary data signal f of PIAl is decreased one by one to detect an appropriate area.

Furthermore, the third excitation voltage adjustment means maintains the excitation voltage determined by the second excitation voltage adjustment means in the upper 8 bits (Dn=1)+) of the D/A converter 21-1, and outputs the P I
A+ 8-bit output line (PB3 to PBo), (
PA3 to PAo) are connected to the lower 8-bit input terminals (D7 to Do) of the D/A converter 21-1, and at the same time, the data of the output of PIA1 is changed accordingly. be. In this way, the output lines of PIA+ (PB3~PBo); ('PA3~PAO)
By changing the 8 bits, the second excitation voltage adjustment means can also adjust the excitation voltage more finely.

As mentioned above, in this example, as in the previous example,
It becomes possible to appropriately charge only the small diameter particles 10.

Next, FIG. 15 is a block diagram of an inkjet recording apparatus according to still another embodiment of the present invention, and (b) of the same figure is:
It is a schematic connection circuit diagram.

In the figure, the same reference numerals as those in the previous figures 4 and 14 indicate equivalent parts, J 1c+-2 is a control device, 20-1 is a digital binary data signal generator, and 21a'+2
l b , 21 C is a D/'A converter.

According to this embodiment, the excitation intensity Jf:
The adjusting means includes an excitation signal generator that generates an excitation signal, a digital binary data signal generator that generates a digital binary data signal that determines the excitation intensity, and a digital binary data signal that receives the same data as the binary data signal. Three sizes of A, B, and C (A>B>C)
A D/A converter that converts to an analog data signal, and an analog data signal output of these three types (D 7 f o f f -1 signal 4 outputs) and adders of 4 and 1. and a synthesizer that receives the excitation signal from the excitation signal generator No. 1 as an input signal and changes the intensity of the excitation signal output depending on the magnitude of the analog data signal, and coarsely adjusts the excitation voltage. The excitation voltage adjustment means of
The digital binary data signal generator operates as a means for varying the digital binary data, with the D/A converter configured to generate an analog data signal of magnitude A for the digital binary data signal X. , the second excitation voltage adjusting means is set to generate an analog data signal B whose magnitude is smaller than A than the D/A converter in response to the binary data signal X; The digital binary data signal generating device operates as a means for changing the digital binary data signal, and the third excitation voltage adjusting means is configured to generate a signal having a magnitude B greater than that of the D/A converter with respect to the binary data signal X. C is further configured to generate an analog data signal of smaller C, and the digital binary data signal generator is configured to operate as a means for varying digital binary data.

That is, in this embodiment, there is one digital binary data signal generator 20-1 and three D/A converters 21a and 21 provided for each excitation voltage adjusting means.
b, 21C and the D/A converters 21a, 21b, 21
The first to third excitation voltages are adjusted by comprising a calo calculator 22 that adds the outputs of c.

In FIG. 15(b), one digital binary data signal generator 20-1 is connected to a latch 1.1 which has a latch function. Latch 2. Although shown as a latch 3, these are built into one unit.

The first excitation voltage adjusting means is a digital lever f.
Nullary data signal generator 20-1 and D/A converter 21
By connecting these, the excitation voltage is adjusted, and after the adjustment is completed, the excitation voltage is fixed.

Next, the second excitation voltage adjustment means is a digital reno (inary data signal generator 20-1 and D/A converter 21b).
By connecting these, the excitation voltage can be similarly adjusted and fixed.

Furthermore, the third excitation voltage adjustment means is composed of a digital binary data signal generator 20-1 and a D/A converter 21C, and by connecting these, the excitation voltage is similarly adjusted and fixed. It is.

At this time, for the digital binary data signal X,
If the output voltages related to the analog data signals A, B, and C of each D/A converter are set so that the output voltage of 21a>output voltage of 21b)2IC output voltage, each of the previous embodiments and Similarly, only the small diameter particles 10 can be appropriately charged.

However, each of the excitation adjustment means in each of the above embodiments is related to an excitation voltage adjustment means, but in addition to this, it is also possible to make the excitation intensity variable, for example, to adjust the current. This can be used as an excitation adjustment means.

It is possible to detect the generation region over a wide range, and to quickly and accurately set the excitation intensity to appropriately charge only small-diameter particles, so it can be said that this invention has remarkable effects.

[Brief explanation of the drawing]

FIG. 1 is a schematic enlarged cross-sectional view of a nozzle part that constitutes a part of an inkjet recording apparatus according to an embodiment of the present invention, and FIG.
The figure is an explanatory diagram of the relationship between the excitation voltage applied to the piezoelectric element of the nozzle and the flight state of the ink particles, and FIG. 3 is a characteristic diagram showing the relationship between the excitation voltage and the length of the ink column of the nozzle. FIG. 4(a) is a block diagram of an inkjet recording apparatus according to an embodiment of the present invention, FIG. 4(b) is a connection circuit diagram thereof, and FIG. FIG. 6 is a diagram of signal waveforms at each part during operation, and FIG. 7 is the excitation voltage and detector output. 1. □,
8, Kawa, Ko, Yuo. The flowchart diagram for Machichi, Figure 9 is -1 The signal waveform diagram of each part during its operation, Figure 1
Figure 0 is an explanatory diagram of the relationship between the excitation voltage and the detector/device output.
Fig. 11 is a flowchart for setting the appropriate excitation voltage, Fig. 12 is a signal waveform diagram of each part during its operation, Fig. 13 is an explanatory diagram of the relationship between the excitation voltage and the detector output, and Fig. 14
(A) of the figure is a block diagram of an inkjet recording apparatus according to another embodiment of the present invention, (B) of the same figure is a schematic connection circuit diagram thereof, and (A) of FIG. A block diagram of an inkjet recording apparatus according to still another embodiment, (b) of the same figure is a schematic connection circuit diagram thereof. DESCRIPTION OF SYMBOLS 1... Nozzle, 2... Ink, 3... High frequency power supply, 4... Piezoelectric element, 6... Nozzle hole, 9... Ink column, lO... Small diameter particle, 11...・Large diameter particles, 12
...Charged deflection electrode, 14...Detector, 17...Excitation signal generator, 19°19-1, 19-2...Control device, 20a, 20b. 20C, 20-1...Digital binary data signal generator, 21a, 21b, 21c, 21-1...
D/A converter, 22... adder, 23... arithmetic unit,
24... Excitation amplifier, 25... Signal processing circuit, 26
. . . first excitation voltage adjustment means, 27 . . . second excitation voltage adjustment means, 28 . . . third excitation voltage adjustment means. Agent Patent attorney Kosaku Fukuda, 1 (and 1 other person:':,:i No. 2 Figure 3 Figure 4 Country (a) 2?α Fifth cause: Desiliconization (Figure 8) 6 Figure 1 ""P)FylJ f&t)4e,""') '(
11th] Bong 10 Kokulip 12 Kuni No. 3 Kuni NJ Subway C

Claims (1)

[Claims] 1. Pressurized ink is ejected through a nozzle, and by adjusting the excitation intensity to the nozzle, large-diameter and small-diameter ink particles are alternately generated, and at least the small-diameter ink particles are generated by a recording signal. In the inkjet recording apparatus configured to be electrically charged, the means for adjusting the excitation intensity includes a first excitation adjustment means for coarsely adjusting the excitation, and a second excitation adjustment for finely adjusting within the excitation adjustment range by the first excitation adjustment means. means and
and a third excitation adjustment means for making very fine adjustments within the excitation adjustment range by the second excitation adjustment means, and each of these adjustment means is sequentially operated to set the excitation intensity to a predetermined value. Features of the in-jet recording device. 2. In the device described in claim 1, the means for adjusting the excitation intensity comprises an excitation signal generator that generates an excitation signal and a digital binary data signal that generates a digital binary data signal that determines the excitation intensity. A signal generator receives the same data of its digital binary data signal and generates two types of sizes A and B (A=AI, A
2. AI) A2) B) Convert to analog data signal D
/A converter, an adder that adds these two types of analog data signals, and receives the analog data signal output of this adder and the excitation signal from the excitation signal generator as input signals, and converts the analog data into It consists of a synthesizer that changes the intensity of the excitation signal output depending on the magnitude of the signal,
The first excitation voltage adjustment means for coarsely adjusting the excitation voltage and the second excitation voltage adjustment means for finely adjusting the excitation voltage have a size A that is larger than the D/A converter for the same digital binary data signal X. the digital binary data signal generator is configured to generate an analog data signal, the digital binary data signal generator operating as a means for coarsely varying the digital binary data and as a means for finely varying the data;
A third excitation voltage adjustment means for finely adjusting the excitation voltage further finely adjusts the excitation voltage by adjusting the D/A
The converter is configured to generate an analog data signal B having a smaller magnitude than A, and the binary data signal generator is configured to operate as a means for further finely varying the digital binary data. An inkjet recording device. 3. In the device described in claim 1, the means for adjusting the excitation intensity comprises an excitation signal generator that generates an excitation signal and a digital binary data signal that generates a digital binary data signal that determines the excitation intensity. a signal generator; a D/A converter for converting the digital binary data signal into an analog data signal; The digital binary data signal generator includes a first excitation voltage adjustment means for roughly changing the intensity of the digital binary data, and a synthesizer for changing the intensity of the digital binary data. The range in which the digital binary data is changed is finely converted into digital binary data.
a second excitation voltage adjustment means for changing the data; and a third excitation voltage adjustment for changing the digital binary data more finely within the range in which the digital binary data is changed by the second excitation voltage adjustment means. An inkjet recording device that forms a means. 4. In the device described in claim 1, the means for adjusting the excitation intensity comprises an excitation signal generator that generates an excitation signal and a digital binary data signal that generates a digital binary data signal that determines the excitation intensity. A signal generator receives the same data of its digital binary data signal and generates three sizes of A, B, C (A) B) C
) A D/A converter that converts into an analog data signal, an adder that adds these three types of analog data signals,
a synthesizer which receives the analog data signal output of the adder and the excitation signal of the excitation signal generator as one input signal, and changes the intensity of the excitation signal output depending on the magnitude of the analog data signal; The first excitation voltage adjustment means for coarsely adjusting the excitation voltage is configured to generate an analog data signal of a magnitude A relative to the digital binary data signal X than the D/A converter; The digital binary data signal generator operates as means for changing digital binary data, and the second excitation voltage adjusting means has a magnitude larger than that of the D/A converter for the binary data signal X. The digital binary data signal generator is configured to generate an analog data signal of B smaller than A, the digital binary data signal generating device operates as a means for changing the digital binary data, and the third excitation voltage adjusting means is configured to generate an analog data signal of B smaller than A. - for the data signal An in-jet recording device configured to operate as a means for changing.