JP2004291457A - Device and method for discharging liquid droplet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a viscosity reduction of a liquid for discharge corresponding to various operation conditions. <P>SOLUTION: A liquid droplet discharging device which discharges liquid droplets from discharge nozzles by selectively supplying a drive signal to an actuator via a switching circuit is equipped with a selector and a control driving means. The selector set between the switching circuit and the actuator alternatively selects the drive signal or a minute vibration drive signal for applying oscillation to the liquid for discharge within the discharge nozzles. The control driving means controls the selector to suitably supply the minute vibration drive signal to the actuator in accordance with a preliminarily set plurality of viscosity reduction modes corresponding to the operation conditions of the liquid droplet discharging device. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a droplet discharge device and method.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. HEI 9-193407 discloses that a signal for oscillation is automatically generated by the head unit without transferring the signal from the host to the head unit when preventing the viscosity of the ink in the head unit from increasing by swinging. An inkjet head driving circuit is disclosed. The inkjet head drive circuit detects a nozzle that has never ejected a droplet in the course of a plurality of ink ejections in the head unit, and oscillates the ink in the nozzle using a micro-vibration signal generated by the head unit. To move.
[0003]
[Patent Document 1]
JP-A-09-193407
[0004]
[Problems to be solved by the invention]
By the way, the above-mentioned conventional ink jet head driving circuit swings the ink during a predetermined recording period (printing period) by discharging the ink, and considers an increase in ink viscosity during a period other than the printing period. It was not done. Generally, in a droplet discharge apparatus using an ink jet head (droplet discharge head), a droplet is discharged onto a recording target by scanning the droplet discharge head with respect to the recording target, so that the droplet is discharged onto the surface of the recording target. Since dimensional recording is performed, the droplet discharge head has various operation periods in addition to the printing period. Even during such various operation periods, an increase in the viscosity of the ejection liquid at the liquid droplet ejection nozzles may occur, and therefore, it is necessary to swing the meniscus according to the characteristics of each operation period.
[0005]
SUMMARY OF THE INVENTION An object of the present invention is to reduce the viscosity of an ejection liquid according to various operation periods of a droplet ejection head.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, there is provided a droplet discharging apparatus for discharging a droplet from a discharging nozzle by selectively supplying a driving signal to an actuator via a switching circuit. A selector that selectively selects a drive signal or a micro-vibration drive signal that oscillates the ejection liquid in the ejection nozzle, and a plurality of reduction signals set in advance corresponding to the operation state of the droplet ejection device. A configuration including control driving means for controlling a selector so as to appropriately supply a micro-vibration driving signal to the actuator according to the viscous mode is adopted.
[0007]
Further, according to the present invention, in a method of discharging a droplet from a discharge nozzle by selectively supplying a drive signal to an actuator, a micro-vibration drive signal for swinging a discharge liquid in the discharge nozzle is generated, A configuration is employed in which the micro-vibration drive signal is supplied to the actuator in accordance with a plurality of viscosity reduction modes set in advance corresponding to the operation state of the droplet discharge device.
[0008]
According to such a means, since the micro-vibration drive signal is supplied to the actuator in accordance with a plurality of viscosity reduction modes set in advance in accordance with the operation state of the droplet discharge device, the viscosity of the meniscus of the discharge liquid is increased. It can be suppressed according to the operation state of the droplet discharge device.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing the overall configuration of the droplet discharge device according to the present embodiment. As shown in FIG. 1, the present droplet discharge device A includes a main body B and a control computer C. The main body B includes a base 1, an X-direction drive shaft 2, a Y-direction drive shaft 3, an X-axis drive motor 4, a Y-axis drive motor 5, a stage 6, a discharge head 7, a control device 8, and the like. C includes a keyboard 10, a computer main body 11, a display unit 12, and the like.
[0010]
The base 1 is a rectangular flat plate having a predetermined area, and an X-direction drive shaft 2 and a Y-direction drive shaft 3 are provided on the surface (upper surface) of the base 1 at right angles to each other. The X-direction drive shaft 2 is composed of a ball screw or the like, and is rotationally driven by an X-axis drive motor 4. The X-axis drive motor 4 is, for example, a stepping motor. The X-axis drive motor 4 rotates the X-direction drive shaft 2 based on a drive signal input from the control device 8 to move the ejection head 7 on the base 1 in the X direction (main direction). (Scanning direction).
[0011]
The Y-direction drive shaft 3 is formed of a ball screw similarly to the X-direction drive shaft 2, and is rotationally driven by a Y-axis drive motor 5. The Y-axis drive motor 5 is, for example, a stepping motor. The Y-axis drive motor 5 rotates the Y-direction drive shaft 3 based on a drive signal input from the control device 8 to move the stage 6 on the base 1 in the Y direction (sub-scanning). Direction). The stage 6 is a rectangular flat plate, and an object W is mounted on the upper surface thereof in a fixed state. The target object W is a target to which the droplets discharged from the discharge head 7 are attached, and are various types of paper, substrates, and the like.
[0012]
The ejection head 7 ejects the ejection liquid stored in the ejection head as droplets from ejection nozzles by using mechanical deformation of a piezoelectric element, and its detailed configuration will be described later. The control device 8 controls and drives the X-axis drive motor 4, the Y-axis drive motor 5, and the ejection head 7 under instructions from the control computer C.
[0013]
Here, as the above-described liquid for ejection (that is, droplets), various liquids are applied according to the application of the present droplet ejection device A, and the viscosity greatly differs depending on the type. The ejection liquid becomes various printing inks when the present droplet ejection apparatus A is used as a printing apparatus, and becomes a conductive material for forming a wiring pattern when used as a pattern wiring apparatus. When used as a forming device, it becomes a transparent resin for forming microlenses, when used as a color filter manufacturing device, becomes a resin for forming a colored layer of a color filter, and when used as an organic EL substrate manufacturing device. An electro-optical material (a fluorescent organic compound exhibiting electroluminescence) that forms a light-emitting pixel is obtained.
[0014]
On the other hand, in the control computer C, the keyboard 10 is used to input various setting information relating to the ejection of droplets to the object W into the computer main body 11. From the keyboard 10, for example, information (thinning mode information) specifying the thinning mode of the present droplet discharge device A is input as one of the various setting information. The viscosity reducing mode information designates the content of the viscosity reducing operation of the discharge liquid during the various operation periods (various operation states) of the droplet discharge device A (that is, the viscosity reducing mode).
[0015]
Here, the thinning operation is to vibrate the ejection liquid by applying a minute vibration waveform (a minute vibration drive signal) to a piezoelectric element which is an actuator for ejecting the ejection liquid. Since the meniscus of the ejection nozzle swings due to the fine vibration of the ejection liquid, the increase in the viscosity of the ejection liquid at the meniscus can be suppressed. Such a viscosity reducing operation is performed at a timing according to the viscosity reducing mode.
[0016]
The computer main body 11 stores the image information of the two-dimensional image drawn on the object W by the droplets discharged from the respective discharge nozzles and the various kinds of setting information as image data a and setting data b. And the setting data b are provided to the control device 8. The display unit 12 is for displaying the various setting information, image information, and the like stored in the computer main body 11 on a screen.
[0017]
Next, FIG. 2 is a block diagram showing a detailed functional configuration of the ejection head 7 and the control device 8. As shown in FIG. 2, the control device 8 includes an I / F 8a, a RAM 8b, a ROM 8c, an arithmetic control unit 8d, a drive signal generation unit 8e, an oscillation circuit 8f, and an I / F 8g.
[0018]
The I / F 8a receives the image data a and the various setting data b provided from the control computer C. The RAM 8b temporarily stores the image data a, the setting data b, and the work data of the arithmetic control unit 8d. The ROM 8c stores a control program processed by the arithmetic and control unit 8d, waveform data c indicating a waveform of the drive signal COM, and various control data necessary for executing the control program.
[0019]
Here, FIG. 3 is a schematic diagram showing a waveform example of the drive signal COM. In this figure, (a) shows a discharge waveform (normal discharge waveform), which is used for normal droplet discharge. Such ejection waveforms have different amplitudes depending on the size of the droplet. (B) shows a rising waveform for changing the bias level of the ejection waveform from the base level to the operation level. When a droplet is ejected by using an ejection waveform, the bias level is raised by a rising waveform as preparation before the droplet is ejected by the ejection waveform. Although not shown in this figure, there is a falling waveform for returning the bias level from the operating level to the base level, contrary to the rising waveform.
[0020]
(C) shows a flushing waveform, which is applied to the ejection head 7 in order to remove foreign matter adhering to the ejection nozzle as preparation for normal ejection of the droplet by the rising waveform. There are two types of flushing waveforms: periodic flushing waveforms and power flushing waveforms.
[0021]
The ROM 8c stores waveform data c corresponding to each of such various waveforms in advance, and includes a viscosity reduction mode data table 8h in which viscosity reduction mode data d is stored. The thinning mode data d is data defining a thinning mode indicating the content of the thinning operation, and corresponds to the thinning mode information (that is, setting data b corresponding to the thinning mode information).
[0022]
FIG. 4 is a schematic diagram showing a table structure of the viscosity reduction mode data table 8h. As shown in this figure, the viscosity reduction mode data d is configured as 4-bit data, and each bit value is set corresponding to the viscosity reduction mode. In the thinning mode data table 8h, different thinning mode data d is assigned to each of a total of ten types of thinning modes.
[0023]
Here, a supplementary explanation of each viscosity reduction mode is as follows. The “outside of printing” at the top corresponds to the viscosity reduction operation in the standby period before ejection, and the reduction in the state where the above-described bias level is set to the base level. It is a viscous movement. “Before printing” is a thinning operation in a state in which the bias level is changed to an operation level from outside of such printing, and is a thinning operation in a period immediately before normal ejection by an ejection waveform. The inside of the printing is a viscosity reducing operation in a period following the above-described pre-printing period, and corresponds to a viscosity reducing operation in a period in which a normal ejection is performed using an ejection waveform.
[0024]
Further, in the viscosity reduction mode data table 8h, as shown in the drawing, three types of viscosity reduction modes in the printing, "A in the printing", "B in the printing", and "C in the printing" are provided. “Intra-printing A” corresponds to a case where, during the in-printing period, only the ejection liquid of the ejection nozzle that does not eject droplets is micro-vibrated, that is, a micro-vibration waveform is applied to the piezoelectric element of the ejection nozzle that does not eject droplets. I do. “Intra-print B” corresponds to a case where a micro-vibration waveform is applied to all the piezoelectric elements 7d1 to 7d180 regardless of whether or not droplets are ejected during the in-print period. “Intra-print C” corresponds to a case where the micro-vibration waveform is applied only to the piezoelectric element of the discharge nozzle that discharges the liquid droplet during the intra-print period.
[0025]
“Always” corresponds to a viscosity reducing operation that is always performed irrespective of the normal operation state of the droplet discharge device A. “Periodic flushing” is a viscosity reducing operation during a flushing operation that is periodically performed using the above-described periodic flushing waveform. On the other hand, the “power flushing” is a method of reducing the viscosity during the power flushing operation that is performed irregularly using a power flushing waveform having a higher peak value than the periodic flushing waveform when the necessity of the flushing operation is determined. Action.
[0026]
In the present droplet discharge device A, cleaning is performed by sliding the discharge nozzle against the wipe material regularly or irregularly. “Cleaning A” is a period corresponding to a periodic cleaning operation among such cleaning operations. On the other hand, “cleaning B” is a period corresponding to an irregular cleaning operation in the cleaning operation. In the cleaning operation, some operation patterns may be set in addition to the regular and irregular periods.
[0027]
As described above, each of the viscosity reducing modes includes one or a plurality of operating states (operating periods) in the droplet discharge device A, that is, each of the non-printing period, the pre-printing period, the in-printing period, the flushing period, and the cleaning period. Is set. Each of these viscosity reduction modes corresponds to viscosity reduction mode information input from the keyboard 10. That is, the thinning mode information input from the keyboard 10 is supplied to the control device 8 as a part of the setting data b by the computer main body 11, and the arithmetic control unit 8d of the control device 8 executes the thinning mode information. The specific thinning mode data d is obtained by searching the thinning mode data table 8h based on the setting data b related to the above.
[0028]
The arithmetic control unit 8d executes the control program based on the image data a and the setting data b, and is composed of ejection pattern data e indicating a droplet ejection pattern of each ejection nozzle and the viscosity reducing mode data d. Generated application pattern data g and motor drive signals for driving the X-axis motor 4 and Y-axis motor 5 are output to the I / F 8g, and waveform data c is obtained from the ROM 8c based on the image data a. And outputs it to the drive signal generator 8e.
[0029]
The ejection pattern data e, which is one of the components of the application pattern data g, is dot pattern data corresponding to each dot forming the image, that is, each dot formed on the target object W by the liquid droplets. The pattern data e is a signal that defines the presence or absence of droplet ejection at each ejection nozzle, that is, the signal that defines the open / close state of each of the switch circuits 7b1 to 7b180. With respect to such ejection pattern data d, the waveform data c defines the size of the droplet for forming each dot, and is sampling data of each drive waveform shown in FIG.
[0030]
The drive signal generation unit 8e determines a deformation state of the piezoelectric elements 7d1 to 7d180 by a drive signal COM for driving the piezoelectric elements 7d1 to 7d180 as actuators based on the waveform data c, that is, by defining a deformation state of the piezoelectric elements 7d1 to 7d180 by a waveform. An analog signal that defines the size of the droplet is generated and output to the I / F 8g. The oscillation circuit 8f generates a reference clock having a predetermined cycle and outputs the generated reference clock to the I / F 8g. The I / F 8g synchronously outputs the applied pattern data g, the drive signal COM, and the motor drive signal to the respective units in synchronization with the reference clock.
[0031]
Here, FIG. 5 is a schematic diagram showing a bit configuration of the applied pattern data g generated by the arithmetic control unit 8d. As shown in this figure, the applied pattern data g is composed of ejection pattern data e of 180 bits and thickening mode data d of 4 bits. Among such application pattern data g, the ejection pattern data e is serial data (180-bit bit string data) corresponding to the number of piezoelectric elements 7d1 to 7d180 (that is, 180 pieces), This defines whether or not ejection is performed.
[0032]
Next, a detailed electrical configuration of the ejection head 7 will be described with reference to FIG.
The ejection head 7 includes a digital processing unit 7a, switch circuits 7b1 to 7b180, a selector 7c, piezoelectric elements 7d1 to 7d180, and the like.
[0033]
The digital processing unit 7a generates opening / closing signals f1 to f180 and a micro vibration selection signal i by performing predetermined logic processing on the applied pattern data g input from the I / F 8g, and converts the opening / closing signals f1 to f180 into respective signals. It outputs the micro-vibration selection signal i to the selector circuits 7b1 to 7b180 and the selector 7c. The digital processing section 7a includes a DC voltage generation section 7e. The DC voltage generator 7e generates a micro-vibration DC voltage h for applying a micro-vibration drive signal to the piezoelectric elements 7d1 to 7d180, and outputs it to the selector 7c.
[0034]
Each of the switch circuits 7b1 to 7b180 is provided corresponding to each of the 180 piezoelectric elements 7d1 to 7d180. One end is commonly connected to the output end of the drive signal COM of the I / F 8g, and the other end is the selector 7c. Are connected to each input terminal. These switch circuits 7b1 to 7b180 open / close in accordance with the values (0 or 1) of the open / close signals f1 to f180. The selector 7c has an output terminal corresponding to the input terminal, and selectively selects either the drive signal COM input from each of the switch circuits 7b1 to 7b180 or the DC voltage h for micro vibration based on the micro vibration selection signal i. And output to each output terminal.
[0035]
One end of each of the piezoelectric elements 7d1 to 7d180 is connected to each output end of the selector 7c, and the other end is connected to GND (that is, ground). The piezoelectric elements 7d1 to 7d180 are provided corresponding to the ejection nozzles, and eject the droplets from the ejection nozzles by being mechanically deformed in response to the application of the drive signal COM.
[0036]
Next, the operation of the liquid droplet ejection apparatus A thus configured will be described in more detail.
[0037]
First, an outline of a droplet discharge operation using a discharge waveform or a flushing waveform will be described. The arithmetic control unit 8d executes the control program based on the image data a and the setting data b provided from the upper control computer C, thereby executing the applied pattern data g, the X-axis motor 4, and the Y-axis motor 5. And generates waveform drive data c from the ROM 8c based on the image data a.
[0038]
The application pattern data g and the motor drive signal thus generated by the arithmetic control unit 8d are output to the I / F 8g, and the waveform data c is output to the drive signal generation unit 8e. The drive signal generation unit 8e generates a drive signal COM by performing D / A conversion on the waveform data c, and outputs the drive signal COM to the I / F 8g. The applied pattern data g, the motor drive signal, and the drive signal COM are synchronized with the reference clock generated by the oscillation circuit 8f, and the digital processing unit 7a, the X-axis motor 4, the Y-axis motor 5, or each of the switch circuits 7b1 to 7b180 Is output synchronously.
[0039]
As described above, the application pattern data g, the motor drive signal, and the drive signal COM are synchronously output from the I / F 8g to each unit, so that the relative movement (that is, the scanning movement) of the discharge head 7 with respect to the object and the liquid from the discharge head 7 Synchronization with drop ejection is realized. That is, the ejection head 7 reciprocates in the X direction (main scanning direction) by driving the X-axis drive motor 4 by the motor drive signal, and the stage 6 (that is, the object W) is moved in the Y-axis by the motor drive signal. When the drive motor 5 is driven, it moves intermittently in the Y direction (sub-scanning direction).
[0040]
Then, the applied pattern data g is processed by the digital processing unit 7a in synchronization with the scanning motion, whereby each of the switch circuits 7b1 to 7b180 is opened and closed in synchronization with the scanning motion, and the selector 7c is operated by the micro vibration selection signal i. By setting to select each of the switch circuits 7b1 to 7b180, the drive signal COM is applied to each of the piezoelectric elements 7d1 to 7d180 in accordance with the operation state of each of the switch circuits 7b1 to 7b180. As a result, a droplet is ejected from the ejection nozzle corresponding to the piezoelectric element to which the drive signal COM is applied in synchronization with the scanning motion, and a two-dimensional image corresponding to the image data a is drawn (recorded) on the object W. Is done.
[0041]
The outline of the droplet discharging operation of the present droplet discharging apparatus A has been described above. The viscosity reducing operation which is a feature of the present droplet discharging apparatus A will be described in more detail with reference to the flowchart shown in FIG. This flowchart shows the viscosity reducing operation of the arithmetic control unit 8d based on the control program. In the following description, as an example, a case will be described in which “in-print A” shown in FIG. 4 is designated as the viscosity reducing mode.
[0042]
First, the arithmetic control unit 8d grasps the designated state of the viscosity reducing mode by confirming the contents of the setting data b (step S1). If the viscosity reduction mode is designated, the viscosity reduction mode data d corresponding to the designated content of the viscosity reduction mode is obtained by searching the viscosity reduction mode data table 8h based on the setting data b (step S2). ).
[0043]
Here, the arithmetic control unit 8d acquires the reduced viscosity mode data d corresponding to “A in printing”, that is, “0011” from the reduced viscosity mode data table 8h. In the process of step S1, if the viscosity reduction mode is not specified, the process of the next step S3 is executed without executing the process of step S2.
[0044]
Subsequently, the arithmetic control unit 8d generates ejection pattern data e based on the image data a (step S3), and combines the ejection pattern data e with the reduced viscosity mode data d obtained from the reduced viscosity mode data table 8h. Thereby, the application pattern data g composed of a total of 184 bits shown in FIG. 5 is generated (step S4). When the generation processing of the application pattern data g is completed, the application pattern data g is output to the I / F 8g (step S5).
[0045]
Further, the arithmetic and control unit 8d acquires the waveform data c (ejection waveform data) of the ejection waveform corresponding to “in-print A” from the ROM 8c (step S6), and outputs the ejection waveform data to the drive signal generation unit 8e. (Step S7). That is, the ejection waveform data is sequentially input to the drive signal generation unit 8e in time series from the arithmetic control unit 8d. The drive signal generation unit 8e sequentially generates a drive signal COM corresponding to the ejection waveform during the in-ejection period by sequentially D / A converting the ejection waveform data, and outputs the drive signal COM to the I / F 8g. The drive signal COM related to the ejection waveform generated in this way is supplied in parallel to one end of each of the switch circuits 7b1 to 7b180 via the I / F 8g.
[0046]
On the other hand, the digital processing unit 7a separates and extracts the ejection pattern data e and the reduced viscosity mode data d from the applied pattern data g, and converts the ejection pattern data e (serial data) into parallel data to thereby open / close signals f1 to f180. And a predetermined logic process is performed on the reduced viscosity mode data d and the ejection pattern data e to generate a micro-vibration selection signal i. Then, it outputs the open / close signals f1 to f180 to the switch circuits 7b1 to 7b180, and outputs the micro vibration selection signal i to the selector 7c.
[0047]
Here, the digital processing unit 7a searches the ejection pattern data e for a bit (open designation bit) for designating that the switch circuit is to be in the open state (that is, for not applying the ejection waveform to the piezoelectric element), and The micro-vibration selection signal i is generated by performing logic processing using the bit array “0011” of the viscosity reduction mode data d for bits. As a result, the micro-vibration selection signal i is a pulse signal that repeatedly applies the DC voltage h for micro-vibration at a predetermined cycle only to the piezoelectric element corresponding to the open designation bit during the printing period. The digital processing unit 7a detects the in-printing period by detecting, for example, the in-printing period based on the supply timing of the application pattern data g from the I / F 8g, and generates the micro-vibration selection signal i.
[0048]
FIG. 7 is a timing chart showing the relationship between the micro vibration selection signal i, the ejection waveform, and each applied waveform. That is, the piezoelectric element corresponding to the open designation bit is generated by the micro-vibration selection signal i, which is a pulse signal, and the micro-vibration DC voltage h, which is a constant DC voltage, during the ejection waveform during the printing period. Each of the micro-vibration waveforms having a predetermined period is inserted. Then, by applying such a micro-vibration waveform to a piezoelectric element that does not discharge droplets, the meniscus of the discharge nozzle oscillates and the increase in viscosity is suppressed.
[0049]
According to the present embodiment, various operation periods in the droplet discharge device A, that is, “out of printing”, “before printing”, “in printing A”, “in printing B”, “in printing C”, “periodic flushing” , "Power flushing", "cleaning A" or "cleaning B" can reduce the viscosity of the ejection liquid.
[0050]
The operation period in which viscosity reduction is most necessary is a period during which droplet ejection is not performed, and is mainly a period other than during printing. In a discharge nozzle that does not discharge liquid droplets during such an operation period, the viscosity of the discharge liquid in the meniscus tends to increase due to the volatilization of the solvent. Although the prior art considers only the viscosity reduction during the in-printing period, in the present embodiment, as described above, not only the viscosity reduction mode corresponding to each operation period in the printing but also the viscosity reduction operation outside the printing period. Is performed, it is possible to suppress the viscosity of the ejection liquid during various operation periods.
[0051]
Further, in the present embodiment, since the in-printing period is provided with three patterns of the viscosity decreasing mode of “in-printing A”, “in-printing B” and “in-printing C”, the ejection liquid is more than the prior art. Effective thinning can be achieved. Further, since the micro-vibration waveform is generated only by switching the micro-vibration DC voltage h by the micro-vibration selection signal i, there is no need to separately provide waveform data for the micro-vibration waveform.
[0052]
Note that the present invention is not limited to the above embodiment, and for example, the following modifications can be considered.
(1) In the above embodiment, the thinning mode data d is composed of 4 bits. However, the number of bits of the thinning mode data d is appropriately set according to the required thinning mode. Not limited.
[0053]
(2) In the above embodiment, the switch circuits 7b1 to 7b180 and the piezoelectric elements 7d1 to 7d180 are connected via the selector 7c, but the buffer amplifiers 7c1 to 7c180 are connected to the output terminals of the switch circuits 7b1 to 7b180. A configuration in which each is provided may be adopted.
[0054]
【The invention's effect】
As described above, according to the present invention, it is possible to suppress the viscosity increase in the meniscus of the discharge liquid in accordance with the operation state of the droplet discharge device. Instead, more effective suppression of thickening in the meniscus can be realized.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating an overall configuration of a droplet discharge device according to an embodiment of the present invention.
FIG. 2 is a block diagram illustrating a functional configuration of a main part of a discharge head 7 and a control device 8 according to an embodiment of the present invention.
FIG. 3 is a schematic diagram illustrating a waveform example of a drive signal COM according to an embodiment of the present invention.
FIG. 4 is a schematic diagram showing a table structure of a viscosity reduction mode data table 8h according to the embodiment of the present invention.
FIG. 5 is a schematic diagram illustrating a bit configuration of applied pattern data g according to an embodiment of the present invention.
FIG. 6 is a flowchart illustrating a viscosity reducing operation according to an embodiment of the present invention.
FIG. 7 is a timing chart showing a relationship among a micro-vibration selection signal i, an ejection waveform, and each applied waveform in one embodiment of the present invention.
[Explanation of symbols]
A: Droplet discharge device
B ... body
C ... Control computer
1. Base
2 ... X direction drive shaft
3 ... Y-direction drive shaft
4 X-axis drive motor
5 ... Y-axis drive motor
6 ... stage
7. Discharge head
7a Digital processing unit
7b1 to 7b180 switch circuit
7c: Selector
7d1 to 7d180... Piezoelectric element
7e DC voltage generator
8 Control device
8a ... I / F
8b RAM
8c ROM
8d: arithmetic control unit
8e: drive signal generation unit
8f oscillating circuit
8g ... I / F
8h: Thinning mode data table
10. Keyboard
11 Computer body
12 Display part

Claims (22)

A droplet discharge device that discharges droplets from a discharge nozzle by selectively supplying a drive signal to an actuator via a switch circuit,
A selector provided between the switch circuit and the actuator, for selectively selecting a drive signal or a micro-vibration drive signal for swinging the ejection liquid in the ejection nozzle;
Control driving means for controlling a selector so as to appropriately supply the microvibration drive signal to the actuator in accordance with a plurality of viscosity reduction modes set in advance corresponding to the operation state of the droplet discharge device. Droplet discharge device. The control driving unit stores the thinning mode data of the bit array corresponding to each of the thinning modes for each of the thinning modes, and specifies the thinning mode data based on the thinning mode specified from the outside. The droplet discharge device according to claim 1, wherein the selector controls the selector. The control drive unit includes a fixedly arranged control device, and a digital processing unit provided on a discharge head that includes a switch circuit and an actuator and moves on an object to discharge droplets,
The control device stores in advance the thinning mode data of the bit array corresponding to each of the thinning modes for each of the thinning modes, specifies the thinning mode data based on the thinning mode specified from the outside, and performs digital control. Supply to the processing unit,
2. The droplet discharge apparatus according to claim 1, wherein the digital processing unit generates a micro-vibration drive signal and controls the selector to apply the micro-vibration drive signal to the actuator based on the viscosity reduction mode data. . The digital processing unit
A DC voltage generator for generating a predetermined DC voltage is provided, and a pulse signal is generated based on the reduced viscosity mode data, and the pulse signal is supplied to the selector as a selection signal and the DC voltage is supplied to the selector as a selected signal. 4. The droplet discharging apparatus according to claim 3, wherein the selector generates a micro-vibration drive signal by the selector and applies the signal to the actuator. The thinning mode is set for a non-printing period, a pre-printing period, an in-printing period, a flushing period, and a cleaning period, which are different operation states of the droplet discharge device. 3. The droplet discharge device according to 1. The droplet discharge device according to claim 1, wherein the droplet is printing ink. The droplet discharge device according to claim 1, wherein the droplet is a conductive material forming a wiring pattern. The droplet discharge device according to claim 1, wherein the droplet is a transparent resin for forming a microlens. The droplet discharge device according to any one of claims 1 to 5, wherein the droplet is a resin for forming a colored layer of a color filter. The droplet discharge device according to claim 1, wherein the droplet is an electro-optical material. 11. The droplet discharge device according to claim 10, wherein the electro-optical material is a fluorescent organic compound exhibiting electroluminescence. A method of discharging a droplet from a discharge nozzle by selectively supplying a drive signal to an actuator,
Generating a micro-vibration drive signal for oscillating the discharge liquid in the discharge nozzle, and applying the micro-vibration drive signal to a plurality of preset viscosity reduction modes corresponding to the operation state of the droplet discharge device. A droplet discharging method comprising supplying the droplet to an actuator. By storing the thinning mode data of the bit array corresponding to each of the thinning modes for each of the thinning modes, and specifying the thinning mode data based on the thinning mode input from the outside, the micro vibration drive signal is generated. 13. The droplet discharging method according to claim 12, wherein the voltage is applied to the actuator according to each of the viscosity decreasing modes. When discharging a droplet by controlling an ejection head that moves on an object to be ejected with an actuator together with an actuator from a fixedly arranged control device,
In the control device, the thinning mode data of the bit array corresponding to each of the thinning modes is stored for each of the thinning modes, and the thinning mode data is specified and discharged based on the thinning mode input from the outside. Supply to the head,
13. The droplet discharge method according to claim 12, wherein the ejection head generates a micro-vibration drive signal based on the viscosity reduction mode data and applies the signal to an actuator. In the ejection head, a predetermined DC voltage is generated, a pulse signal is generated based on the reduced viscosity mode data, the pulse signal is supplied to the selector as a selection signal, and the DC voltage is supplied to the selector as a selected signal. 15. The method according to claim 14, wherein a micro-vibration drive signal is generated and applied to an actuator. The thinning mode is set for a non-printing period, a pre-printing period, an in-printing period, a flushing period, and a cleaning period, which are different operation states of the droplet discharge device. 2. The droplet discharging method according to 1. 17. The droplet discharging method according to claim 10, wherein the droplet is printing ink. 17. The droplet discharging method according to claim 10, wherein the droplet is a conductive material for forming a wiring pattern. 17. The droplet discharging method according to claim 10, wherein the droplet is a transparent resin for forming a microlens. 17. The droplet discharging method according to claim 10, wherein the droplet is a resin for forming a colored layer of a color filter. 17. The droplet discharging method according to claim 10, wherein the droplet is an electro-optical material. 22. The droplet discharging method according to claim 21, wherein the electro-optical material is a fluorescent organic compound exhibiting electroluminescence.

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