JP4432201B2 - Ink ejection apparatus driving method, control apparatus, and storage medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving method and a control device of an ink jet apparatus using an ink jet method, and a storage medium.
[0002]
[Prior art]
Conventionally, as an ink jet ink ejecting apparatus, the volume of the ink flow path is changed by deformation of piezoelectric ceramics, and when the volume decreases, ink in the ink flow path is ejected as droplets from the nozzle, and ink is introduced when the volume increases. An apparatus in which ink is introduced into an ink flow path from a mouth is known. In this type of recording head, a plurality of ink flow paths separated by piezoelectric ceramic partition walls are formed, and ink supply means such as an ink cartridge is connected to one end of the plurality of ink flow paths, and the other end is connected to the other end. Is provided with ink ejection nozzles (hereinafter referred to as nozzles), and by reducing the volume of the ink flow path by deformation of the partition wall according to print data, ink droplets are ejected from the nozzles onto the recording medium, Characters and figures are recorded.
[0003]
In this type of ink ejecting apparatus, a drop-on-demand type head that ejects ink droplets is widely used because of its high ejection efficiency and low running cost. As a drop-on-demand type, there is a shear mode type using a piezoelectric material as disclosed in Japanese Patent Laid-Open No. 63-247051. A cross-sectional view of one example is shown in FIG. The ink-jet head 600 includes an actuator substrate 601 and a cover plate 602 in which a plurality of slender groove-shaped ink flow paths 613 extending in the thickness direction of the paper and a space 615 that does not contain ink are arranged across a side wall 617. The side wall 617 is composed of a lower wall 611 polarized in the arrow P1 direction in the lower half and an upper wall 609 polarized in the arrow P2 direction in the upper half. Each ink channel 613 has a nozzle 618 at one end and a manifold for supplying ink to the other end. The end of the space 615 on the manifold side is closed so that ink does not enter. Electrodes 619 and 621 are provided as metallization layers on both side surfaces of each side wall 617. Specifically, a channel electrode 619 is provided on the side wall 617 on the ink channel 613 side, and all the channel electrodes 619 are grounded. An in-space electrode 621 is provided on the side wall 617 on the space 615 side. In FIG. 7, adjacent in-space electrodes 621 in the same space 615 are insulated from each other, and adjacent in-space electrodes 621 across the ink flow path 613 are electrically connected to provide an actuator drive signal. Connected to the control device 625 shown.
[0004]
7 is applied to the space electrode 621 adjacent to the ink flow path 613 with the ink flow path 613 interposed therebetween, so that the side wall 617 is deformed in a piezoelectric thickness direction in the direction in which the volume of the ink flow path 613 is increased. For example, as shown in FIG. 6, when the ink flow path 613b is driven, the voltage E (V) is applied to the adjacent space electrodes 621c and d across the ink flow path 613b with all the flow path electrodes 619 grounded. ) Is applied, an electric field in the direction of arrow E is generated on the side walls 617c and d, and the side walls 617c and d undergo a piezoelectric thickness slip deformation in the direction of increasing the volume of the ink flow path 613b. At this time, the pressure in the ink flow path 613b including the vicinity of the nozzle 618b decreases. This state is maintained for a one-way propagation time T in the pressure wave ink channel 613. In the meantime, ink is supplied from a manifold (not shown).
[0005]
The one-way propagation time T is a time required for the pressure wave in the ink flow path 613 to propagate in the longitudinal direction of the ink flow path 613. The length L of the ink flow path 613 and the ink flow path 613 T = L / a is determined by the speed of sound a in the ink inside.
[0006]
According to the pressure wave propagation theory, the pressure in the ink flow path 613 is reversed and turned to a positive pressure just after T time has elapsed from the application of the voltage, but the pressure is applied to the space electrodes 621c and d substantially in accordance with this timing. The applied voltage is returned to 0 (V).
[0007]
Then, the side walls 617c and d return to the state before deformation (FIG. 5), and pressure is applied to the ink. At that time, the pressure turned positive and the pressure generated when the side walls 617c and d return to the state before deformation are added together, and a relatively high pressure is generated in a portion near the nozzle 618b of the ink flow path 613b. Ink droplets are ejected from the nozzle 618b.
[0008]
More specifically, if the time from when the voltage is applied until the voltage is returned to 0 (V) is deviated from the one-way propagation time T, the ink efficiency is lowered because the ink droplets are ejected, and the one-way propagation time T In general, when the energy efficiency is increased, for example, when it is desired to drive at a voltage as low as possible, until the voltage is returned to 0 (V). It is desirable that the time is equal to the one-way propagation time T or at least approximately an odd multiple.
[0009]
[Problems to be solved by the invention]
Conventionally, in this type of ink-jet head 600, there is a demand for minimizing the volume of ink droplets ejected for high-quality printing such as photographs. For this purpose, the ink droplet is ejected by the ejection pulse, and before the ink droplet is completely ejected, a part of the ink is pulled back into the ink flow path, and the droplet for reducing the size of the ink droplet. Some ideas have been made, such as adding a miniaturized pulse.
[0010]
However, the ejection of the small ink droplets by the driving method using the two pulses of the ejection pulse and the droplet miniaturization pulse described above does not suppress the residual pressure oscillation in the ink flow path, and therefore, at a high printing frequency. In this driving, the ejection becomes unstable, and unnecessary ink droplets are ejected, bent, or not ejected, and the print quality is deteriorated.
[0011]
The present invention has been made in order to solve the above-described problems, and is capable of stably ejecting small ink droplets of 20 pl (picoliter) or less even at a high printing frequency drive, and capable of high-quality printing at high speed. It is an object of the present invention to provide a driving method and a control device for an ejection device, and a storage medium.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is directed to a nozzle that ejects ink droplets, an ink channel that is connected to the nozzle and filled with ink, and a volume of the ink channel is increased or decreased. An actuator that generates a pressure wave in the ink flow path and a control device that applies an ejection pulse for ejecting ink droplets from the nozzle to the actuator, ejects ink droplets having a volume of 20 pl or less. In the driving method of the ink ejecting apparatus, when there is no ejection command immediately before and after one dot, the ejection pulse A and the ejection pulse A have the same peak value, and the ejected ink droplets are ejected from the nozzle. Before leaving the ink droplet, the ink droplet is ejected by using the drive waveform 1 including a droplet miniaturization pulse for pulling back a part of the ink droplet into the ink flow path. In this case, the injection pulse B has the same peak value as that of the injection pulse A, and the injection stabilization pulse that has the same peak value as the injection pulse A and suppresses residual vibration due to the injection pulse B. An ink ejection apparatus driving method characterized by ejecting ink droplets using a driving waveform 2 as described above.
[0013]
In this method, when the print command is continuous (that is, at a high print frequency drive), the ink droplet is ejected with the drive waveform 2 having the ejection stabilization pulse, and when the print command is not continuous, the droplet is ejected. By ejecting ink droplets with a drive waveform 1 having a miniaturized pulse, ink can be ejected stably even in the case of high-frequency driving.
[0014]
According to the invention of claim 2, in the method of claim 1, when the time during which the pressure wave propagates one way in the ink flow path is T, the wave width of the ejection pulse A is substantially equal to the T. The wave width of the droplet miniaturization pulse is in the range of 0.2 to 0.3 times T, and the time between the ejection pulse A and the droplet miniaturization pulse is The width of the injection pulse B is in the range of 0.4 to 0.6 times T, and the wave width of the injection pulse B is in the range of 0.5 to 0.7 times T. The wave width is in the range of 0.2 to 0.3 times T, and the time between the injection pulse B and the injection stabilization pulse is 2.0 to 2.2 times T. Within range.
[0015]
In this way, by setting the widths and additional timings of all the pulses, the difference in ink ejection speed and droplet volume between the drive waveform 1 and the drive waveform 2 is reduced, and the ejection stability under each condition. Can be realized.
[0016]
According to a third aspect of the present invention, the storage means for storing the driving waveform 1 and the driving waveform 2 is discriminated from whether or not there is an injection command both immediately before and after one dot, and when there is no injection command. The above driving method is realized by a control device including output means for applying the driving waveform 1 to the actuator, and otherwise driving the driving waveform 2 to the actuator.
[0017]
According to a fourth aspect of the present invention, the drive waveform 1 and the drive waveform 2 are stored in a storage medium storing a program used in a personal computer or the like when print data is output from the personal computer or the like to the ink ejecting apparatus. To determine whether or not there is an injection command immediately before and after one dot. If there is no injection command, the drive waveform 1 is set. Otherwise, the drive waveform 2 is set to The above driving method is realized by applying to the actuator.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. The configuration of the mechanical part in the ink droplet ejecting apparatus of the present embodiment is the same as that shown in FIG.
[0019]
An example of specific dimensions of the ink droplet jet head 600 will be described. The length L of the ink flow path 613 is 6.0 mm. The nozzles 618 are 26 μm in diameter on the ink droplet ejection side, 40 μm in diameter on the ink flow path 613 side, and 75 μm in length. The viscosity of the ink used in the experiment at 25 ° C. is about 2 mPa · s, and the surface tension is 30 mN / m. The ratio L / a (= T) between the speed of sound a in the ink in the ink flow path 613 and L was 9.0 μsec.
[0020]
FIG. 1 shows a driving waveform for stably ejecting fine droplets of 20 pl or less.
A driving waveform 1 shown in FIG. 1A is a driving waveform for stably ejecting a fine droplet of 20 pl or less, and the number attached is a one-way propagation time T of the pressure wave in the ink flow path 613. Is the ratio of the length of time to.
[0021]
The drive waveform 1 includes an ejection pulse A for ejecting an ink droplet and a droplet miniaturization pulse C for reducing the volume of the ink droplet ejected by the ejection pulse A. For example, before the ink droplet ejected by the ejection pulse A completely leaves the nozzle 618, the side wall 617 is deformed in the direction of expanding the volume of the ink flow path 613 by the miniaturization pulse C, and the rear portion of the ink droplet Is pulled back into the ink flow path 613. The peak value (voltage value) of all the pulses is E (V) (for example, 17 (V) at 25 ° C.). The width Wa of the ejection pulse A coincides with the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 9.0 μsec. The width Wc of the droplet miniaturization pulse corresponds to 0.2 to 0.3 times the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 1.8 to 2.7 μsec. Further, the time Wb between the ejection pulse A and the droplet miniaturization pulse coincides with 0.4 to 0.6 times the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 3.6 to 5 .4 μsec.
[0022]
The results of experiments conducted to determine the appropriate range of these timings will be described. The table shown in FIG. 2 shows the time Wb between the ejection pulse A and the droplet miniaturization pulse while the width Wa of the ejection pulse A is fixed to a value that matches the one-way propagation time T of the pressure wave in the ink flow path 613. Is changed in increments of 0.05 from 0.3 to 0.7 times the one-way propagation time T of the pressure wave in the ink channel 613, and the width Wc of the droplet miniaturization pulse is changed to the pressure in the ink channel 613. The evaluation results when the wave one-way propagation time T is changed in increments of 0.05 to 0.1 to 0.4 times are shown. As an evaluation method, the injection state when continuously driven at a voltage E = 17 V and a frequency of up to 7.5 kHz is observed. When stably ejecting droplets of 20 pl or less, ◯, when accompanied by bending, Δ The case where the injection was unstable and accompanied by splashing was defined as X.
[0023]
From this result, the time Wb between the ejection pulse A and the droplet miniaturization pulse is set within a range of 0.40 to 0.60 times the one-way propagation time T of the pressure wave in the ink flow path 613, and the droplet It can be seen that when the width Wc of the miniaturization pulse is set in the range of 0.20 to 0.30 times the one-way propagation time T of the pressure wave in the ink flow path 613, stable ejection is performed. The flying speed of the ejected ink droplet at this time was about 6.0 m / s and the volume was about 15 pl.
[0024]
In the case of the driving waveform 1, the jet becomes unstable when the printing frequency is higher than 7.5 kHz, and the driving method using only the driving waveform 1 prints at a high frequency such as 10 kHz and 15 kHz. I couldn't.
[0025]
A drive waveform 2 shown in FIG. 1B is a drive waveform for stably ejecting a fine droplet of 20 pl or less even at a high frequency, and the number attached is one way of a pressure wave in the ink flow path 613. It is the ratio of the length of time to the propagation time T. An ejection pulse B for ejecting ink droplets and an ejection stabilization pulse D for suppressing pressure oscillation in the ink flow path 613 generated by ejection of ink droplets by the ejection pulse B are included. For example, the side wall 617 is deformed in the direction in which the volume of the ink flow path 613 is expanded by the stabilization pulse D at the timing when the pressure in the ink flow path 613 increases, and then the timing at which the pressure in the flow path 613 decreases. By returning the side wall 617, pressure fluctuation in the ink flow path 613 is suppressed.
[0026]
The crest value (voltage value) of all pulses of the drive waveform 2 is E (V) (for example, 17 (V) at 25 ° C.). The width Wd of the ejection pulse B corresponds to 0.5 to 0.7 times the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 4.5 to 6.3 μsec. The width Wf of the ejection stabilization pulse D corresponds to 0.2 to 0.3 times the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 1.8 to 2.7 μsec. The time We between the ejection pulse B and the ejection stabilization pulse D coincides with 2.0 to 2.2 times the one-way propagation time T of the pressure wave in the ink flow path 613, that is, 18.0 to 19 .8 μsec.
[0027]
The results of experiments conducted to determine the appropriate range of these timings will be described. First, the reason why the wave width Wd of the ejection pulse B is set to 0.5 to 0.7 times the one-way propagation time T of the pressure wave in the ink flow path 613 is that the driving voltage is the same as that of the driving waveform 1 described above. In addition, this is to make the flying speed and volume of the ink droplets as close as possible. That is, in the drive waveform 2, unlike the droplet miniaturization pulse C, a pulse that pulls the ejected ink back into the ink flow path is not used, so the wave width Wd of the ejected pulse B is equal to the pressure wave in the ink flow path 613. If it coincides with the one-way propagation time T, both the flying speed and the ink droplet volume become too large. However, the wave width Wd of the ejection pulse B is set to 0.5 to 0.7 times the one-way propagation time T of the pressure wave in the ink flow path 613. For example, the drive waveform 1 has a flying speed of 6.0 m / s and a volume of 15 pl. When using the same drive voltage as in the case of the above, it was found that the flying speed and ink droplet volume close to the driving waveform 1 with a flying speed of 6.0 to 6.5 m / s and a volume of 15 to 19 pl were obtained.
[0028]
The table shown in FIG. 3 shows that the width We of the ejection pulse B is fixed to a value corresponding to 0.6 times the one-way propagation time T of the pressure wave in the ink flow path 613 while the width We of the ejection pulse B is fixed. The pressure wave in the path 613 is changed by 0.05 times from 1.85 to 2.35 times the one-way propagation time T of the pressure wave, and the width Wf of the ejection stabilization pulse D is changed to one-way of the pressure wave in the ink flow path 613. The evaluation results when changing the propagation time T in increments of 0.05 to 0.1 to 0.4 times are shown. As an evaluation method, the ejection state when continuously driven at a voltage E = 17 V and a frequency of 10 to 15 kHz is observed, and when droplets of 20 pl or less are stably ejected, ◯, when accompanied by bending, Δ is ejected. X was defined as unstable and accompanied by splashing.
[0029]
From this result, the time We between the ejection pulse B and the droplet miniaturization pulse is set within the range of 2.0 to 2.2 times the one-way propagation time T of the pressure wave in the ink flow path 613, and the ejection stability. It can be seen that when the width Wf of the activating pulse is set in the range of 0.20 times to 0.30 times the one-way propagation time T of the pressure wave in the ink flow path 613, stable ejection is performed. The flying speed of the ejected ink droplet at this time was about 6.3 m / s and the volume was about 18 pl.
[0030]
When this driving waveform 2 is used, it can be stably ejected up to a higher printing frequency than the driving waveform 1, but it has been found that the volume of ejected ink droplets increases by about 20%. A description will be given of a method of driving the driving waveform 1 capable of ejecting minute ink droplets at a low printing frequency and the driving waveform 2 capable of ejecting stably even at a high frequency although the volume is slightly increased.
[0031]
If the print command is continuous and dots are formed on the recording medium, one dot cannot be distinguished. Therefore, even if the ink droplet becomes larger and the dot diameter becomes larger. It doesn't matter much. Accordingly, it can be seen that the drive waveform 2 that can be stably ejected at a high printing frequency although the volume is slightly large is preferably used when printing commands are continuous. On the other hand, when the print commands are not continuous and dots are formed sparsely on the recording medium, the graininess of the dots becomes a problem, so each dot is required to be smaller. . Accordingly, it can be seen that the drive waveform 1 is suitable for continuous ejection at a high printing frequency, but is unstable, but dots are sparse, that is, when driving at a substantially low printing frequency, smaller droplets can be ejected.
[0032]
As described above, as shown in FIG. 4, when there is no print command immediately before and after one dot, an ink droplet is ejected using the drive waveform 1 and immediately before one dot or If there is a print command immediately after that and ink droplet ejection continues, printing is performed at a high print frequency of 10 to 15 kHz by controlling the ink droplet to be ejected using drive waveform 2 Is also stable, and high-speed and high-resolution printing is possible.
[0033]
As described in detail above, when the print command is continuous when the ink droplet has a volume of 20 pl or less, the ink droplet is applied with the drive waveform 2 having the ejection stabilization pulse D. In the case where the ejection command is not continuous, the ink droplets are ejected with the drive waveform 1 having the droplet miniaturization pulse C, so that the ink can be ejected stably even in the case of driving at a high printing frequency.
[0034]
Next, an embodiment of a control device for realizing the various drive waveforms as described above will be described with reference to FIGS. The control device 625 shown in FIG. 7 includes a charging circuit 182, a discharging circuit 184, and a pulse control circuit 186. The piezoelectric material of the side wall 617 and the electrodes 619 and 621 are equivalently represented by a capacitor 191.
[0035]
The input terminals 181 and 183 are input terminals for inputting a pulse signal for setting the voltage applied to the electrode 621 in the space 615 to E (V) and 0 (V), respectively. The charging circuit 182 includes resistors R101, R102, R103, R104, R105, and transistors TR101, TR102.
[0036]
When an ON signal (+5 V) is input to the input terminal 181, the transistor TR 101 becomes conductive through the resistor R 101, and current flows from the positive power source 187 through the resistor R 103 to the emitter from the collector of the transistor TR 101. Therefore, the voltage division across the resistors R104 and R105 connected to the positive power supply 187 increases, the current flowing through the base of the transistor TR102 increases, and the emitter and collector of the transistor TR102 are conducted. For example, a voltage of 16 (V) from the positive power supply 187 is applied to the capacitor 191 via the collector and emitter of the transistor TR102 and the resistor R120.
[0037]
Next, the discharging circuit 184 will be described. The discharging circuit 184 includes resistors R106 and R107 and a transistor TR103. When an ON signal (+5 V) is input to the input terminal 183, the transistor TR103 is turned on via the resistor R106, and the resistor R120 side terminal of the capacitor 191 is grounded via the resistor R120. Therefore, the charge applied to the side wall 617 shown in FIGS. 5 and 6 is discharged.
[0038]
Next, the pulse control circuit 186 that generates pulse signals input to the input terminal 181 of the charging circuit 182 and the input terminal 183 of the discharging circuit 184 will be described. The pulse control circuit 186 is provided with a CPU 110 that performs various arithmetic processes. The CPU 110 generates an on / off signal according to the control program and timing of the RAM 112 and the pulse control circuit 186 that store print data and various data. A ROM 114 storing sequence data is connected. Here, the ROM 114 is provided with an ink droplet ejection control program storage area 114A and a drive waveform data storage area 114B, as shown in FIG. . Therefore, the data of the driving waveforms 1 and 2 are stored in the driving waveform data storage area 114B, and the relationship between the situation immediately before and immediately after one dot shown in FIG. This is stored in the control program storage area 114A.
[0039]
Further, the CPU 110 is connected to an I / O bus 116 for exchanging various data, and a print data receiving circuit 118 and pulse generators 120 and 122 are connected to the I / O bus 116. The output of the pulse generator 120 is connected to the input terminal 181 of the charging circuit 182, and the output of the pulse generator 122 is connected to the input terminal 183 of the discharging circuit 184.
[0040]
The CPU 110 controls the pulse generators 120 and 122 according to the data stored in the control program storage area 114A and the drive waveform data recording area 114B of the ROM 114. Therefore, it is possible to discriminate the situation immediately before and after one dot in the received print data and selectively output the driving waveform 1 or 2 corresponding thereto.
[0041]
Note that the pulse generators 120 and 122, the charging circuit 182 and the discharging circuit 184 are provided in the same number as the number of nozzles. In the present embodiment, the control of one nozzle has been described as a representative, but the same control applies to the control of other nozzles.
[0042]
FIGS. 9A and 9B are functional block diagrams of the control device 625 and show the flow of signals of the print command. In FIG. 2A, a print command is given to a driver circuit as a control signal from driver software in a personal computer or the like. Based on this, the driver circuit reads various data stored in the ROM, generates a drive signal, and drives the actuator. Here, the driver circuit determines whether or not droplet ejection has occurred before each dot and whether or not there is next droplet ejection and changes the drive waveform as described above.
[0043]
In FIG. 4B, the print command is converted into the drive waveform 1 or 2 with reference to the table of FIG. 4 by driver software in a personal computer or the like, and the control signal is given to the driver circuit. Drive signal, thereby driving the actuator. In this example, a storage medium storing the table of FIG. 4 and drive waveform data is provided as driver software.
[0044]
While the present embodiment has been described above, the present invention is not limited to this. For example, the wave width, number, combination, and the like of the ejection pulse, droplet stabilization pulse, and droplet miniaturization pulse constituting the drive waveform can be freely modified.
[0045]
Further, in this embodiment, the actuator uses a shear mode type piezoelectric material, but the piezoelectric material may be laminated and a pressure wave may be generated by deformation in the lamination direction. Any device that generates pressure waves in the flow path can be used.
[0046]
【The invention's effect】
As described above, according to the present invention, in the printing of minute droplets having an ink droplet volume of 20 pl or less, if there is no continuous printing command, printing at a high printing frequency is unstable. The driving waveform 1 that can stably eject micro droplets is used at a low printing frequency, and at the time of continuous printing, driving is performed using the driving waveform 2 that can be stably ejected although the ink droplet volume is slightly large. Enables high resolution printing.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a driving waveform of an ink ejecting apparatus according to an embodiment of the invention.
FIG. 2 is a diagram showing a result of an injection test performed for obtaining an optimum condition of drive waveform 1 according to the present embodiment.
FIG. 3 is a diagram showing a result of an injection test performed for obtaining an optimum condition of a driving waveform 2 of the present embodiment.
FIG. 4 is a diagram illustrating conditions using a drive waveform according to the present embodiment.
FIG. 5 is a cross-sectional view showing an ink jet head used in the present embodiment.
6 is a diagram for explaining the operation of the inkjet head of FIG. 5;
FIG. 7 is a diagram illustrating a control device according to the present embodiment.
FIG. 8 is a diagram showing a storage area of the control device of FIG. 7;
9A and 9B are functional block diagrams of a control device. FIG.
[Explanation of symbols]
1 Drive waveform (for non-continuous operation)
2 Drive waveform (for continuous use)
600 Inkjet head
613 Ink channel
625 controller

Claims (4)

A nozzle that ejects ink droplets, an ink channel that is connected to the nozzle and filled with ink, an actuator that generates a pressure wave in the ink channel by increasing or decreasing the volume of the ink channel, and an ink liquid A controller for applying an ejection pulse for ejecting a droplet from the nozzle to the actuator, and a method for driving an ink ejection device that ejects an ink droplet having a volume of 20 pl or less.
When there is no ejection command both immediately before and after one dot, the ejection pulse A and the peak value of the ejection pulse A are the same, and the ejection of the ink droplet before the ejected ink droplet leaves the nozzle. Ink droplets are ejected using a drive waveform 1 consisting of a droplet miniaturization pulse for pulling back part of the ink into the ink flow path,
In other cases, the injection pulse B having the same peak value as the injection pulse A and a small pulse width, and the injection stabilization pulse having the same peak value as the injection pulse A and suppressing residual vibration due to the injection pulse B A method of driving an ink ejecting apparatus, wherein ink droplets are ejected using a driving waveform 2 comprising: When the time during which the pressure wave propagates one way through the ink flow path is T, the wave width of the ejection pulse A is substantially equal to the T, and the wave width of the droplet miniaturization pulse is 0 of the T In the range of 2 to 0.3 times, and the time between the ejection pulse A and the droplet miniaturization pulse is in the range of 0.4 to 0.6 times the T;
The wave width of the injection pulse B is in the range of 0.5 to 0.7 times the T, and the wave width of the injection stabilization pulse is in the range of 0.2 to 0.3 times the T. 2. The ink ejection according to claim 1, wherein a time between the ejection pulse B and the ejection stabilization pulse is in a range of 2.0 times to 2.2 times the T. 3. Device driving method. A nozzle that ejects ink droplets, an ink channel that is connected to the nozzle and filled with ink, an actuator that generates a pressure wave in the ink channel by increasing or decreasing the volume of the ink channel, and an ink liquid An ink ejection device for ejecting ink droplets having a volume of 20 pl or less, comprising a control device that applies to the actuator an ejection pulse for ejecting droplets from the nozzle;
Droplet miniaturization for returning a part of the ejected ink droplet A to the ink flow path before the ejected ink droplet leaves the nozzle, and has the same peak value as the ejected pulse A A drive waveform 1 composed of pulses, an injection pulse B having the same peak value as that of the injection pulse A, and an injection pulse B having the same peak value as the injection pulse A and suppressing residual vibration due to the injection pulse B. Storage means for storing a drive waveform 2 composed of an activating pulse;
It is determined whether or not there is an injection command immediately before and after one dot. If there is no injection command, the drive waveform 1 is applied to the actuator, and otherwise, the drive waveform 2 is applied to the actuator. And an output means. Ink comprising a nozzle that ejects ink droplets, an ink channel that is connected to the nozzle and filled with ink, and an actuator that generates a pressure wave in the ink channel by increasing or decreasing the volume of the ink channel In the ejection device, a storage medium storing a program for outputting an ejection pulse for ejecting an ink droplet having a volume of 20 pl or less from the nozzle to the actuator,
Droplet miniaturization for returning a part of the ejected ink droplet A to the ink flow path before the ejected ink droplet leaves the nozzle, and the crest value is the same as the ejected pulse A A drive waveform 1 composed of a pulse, an injection pulse B having the same peak value as that of the injection pulse A, and an injection pulse B having a small wave width and the same pulse value as the injection pulse A and suppressing residual vibration due to the injection pulse B A drive waveform 2 consisting of a singulated pulse,
It is determined whether or not there is an injection command immediately before and after one dot, and when there is no injection command, the drive waveform 1 is applied to the actuator, and otherwise, the drive waveform 2 is applied to the actuator. The storage medium described above.

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