JPH10250066A - Driving method of printer device - Google Patents

Abstract

[PROBLEMS] To enable dot formation with an appropriate ink density even at the time of low-density printing, and to perform a reliable mixed-discharge operation from a low density to a high density. SOLUTION: A first pressure chamber into which a measurement medium is introduced, a first nozzle communicating therewith, a second pressure chamber into which a discharge medium is introduced, a second nozzle communicating therewith, A first pressure application unit of a printer device having a first pressure application unit for extruding a medium and a second pressure application unit for ejecting an ejection medium is caused to perform an extrusion operation from a steady state, and a second operation is performed from a first nozzle. After the quantitation medium is oozed toward the nozzle of the second nozzle and the quantitation medium is brought into contact with the ejection medium near the tip of the second nozzle, the second pressure application unit performs the ejection operation from the steady state to perform the quantification medium. When mixing and discharging the ink and the discharge medium, the ratio of the change in the amount of extrusion in the extrusion operation of the first pressure applying means is changed so as to increase as the amount of extrusion decreases.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method of driving a printer device for mixing and discharging a fixed amount medium and a discharge medium. More specifically, the present invention relates to a driving method of a printer device which enables a reliable mixing / ejection operation to be performed by defining a driving method of a quantitative operation in a mixing operation of a measurement medium and an ejection medium.

[0002]

2. Description of the Related Art In recent years, documents such as desktop publishing have been actively used in offices and the like. Recently, not only characters and figures but also color images such as photographs have been developed. There has been an increasing demand for outputting natural images together with characters and figures. Along with this, it is required to print a high-quality natural image, and gradation expression by halftone display is important.

A so-called on-demand type in which ink droplets are ejected from nozzles only when necessary during printing in accordance with a control signal in accordance with a recording signal and are adhered to a recording material such as paper or film to perform recording. In recent years, the printer device has been rapidly spreading because of the possibility of miniaturization and cost reduction.

As described above, various methods have been proposed for discharging ink droplets from nozzles.
A method using a piezo element or a method using a heating element is generally used. The former is a method in which pressure is applied to ink to discharge it by deformation of a piezo element. The latter method is a method in which the ink is heated and vaporized by a heating element and the ink is ejected at a pressure of bubbles generated.

Various methods have been proposed as methods for simulating the above-described gray scale display by halftone display with an on-demand type printer apparatus which discharges the above-described ink droplets. That is, the first method is to control the size of a droplet to be ejected by changing the voltage or pulse width of a voltage pulse applied to a piezo element or a heating element, and to express gradation by changing the diameter of a print dot. Can be

However, in the first method, if the voltage or pulse width applied to the piezo element or the heating element is too low, the ink will not be ejected, so that the minimum droplet diameter is limited. It has the disadvantage of being very difficult to express, especially at low concentrations. Therefore,
It is unsatisfactory to print out natural images.

As a second method, one pixel is constituted by a matrix of, for example, 4 × 4 dots without changing the dot diameter, and the gradation is expressed by a so-called dither method or the like in units of the matrix. There is a method of performing.

However, also in the second method, when one pixel is constituted by a 4 × 4 matrix, a density of 17 gradations can be expressed. For example, the dot density is the same as that of the first method. When printed, the resolution is reduced to 1/4, and the roughness is conspicuous, which is also unsatisfactory for printing out a natural image.

In order to clarify the problems of the conventional on-demand type printer apparatus which discharges only ink, the present inventors have proposed, for example, Japanese Patent Laid-Open No. Hei 5-201024.
As shown in the publication, the ink and a diluent, which is a transparent solvent, are mixed at a predetermined mixing ratio immediately before ejection to obtain a diluted ink, and the diluted ink is immediately ejected from a nozzle and adhered to a recording material. A two-liquid mixing type printer device for performing recording has been proposed. Hereinafter, among such methods, the ink is used as a measurement medium, the diluent is used as a discharge medium, and the ink as a measurement medium is mixed with a diluent as a discharge medium to obtain diluted ink, and the discharge medium is discharged. A method of performing recording by using a carrier jet method is described. However, in the above-described printer apparatus, there is no problem even if the diluting liquid is used as the measurement medium and the ink is used as the ejection medium.

In such a printer of the carrier jet system, it is possible to control the density of the diluted ink droplets to be ejected and to change the density for each dot to be printed, thereby causing deterioration in resolution. It is possible to print out a natural image rich in intermediate gradations without any problem.

Incidentally, such a two-liquid mixing type printer device has a first pressure chamber into which a quantitative medium is introduced, and a second pressure chamber into which a discharge medium is introduced. A first nozzle communicating with the first pressure chamber and a second nozzle communicating with the second pressure chamber are opened adjacent to each other, and a predetermined amount of the fixed amount medium is discharged from the first nozzle to the nozzle opening surface. Is transmitted to the second nozzle so as to bleed toward the second nozzle, and is brought into contact with the discharge medium filled in the vicinity of the tip of the second nozzle, thereby discharging a fixed amount of the discharge medium from the second nozzle. And a printer device that discharges a discharge medium as a mixed solution. That is, in this printer device, the ink concentration of the mixed droplet is changed for each dot by mixing a fixed amount of the diluting liquid or ink serving as the discharge medium while changing the amount of the ink or diluting liquid which becomes the measuring medium. To represent the gradation.

[0012]

In such a printer device, first pressure applying means for applying pressure to the fixed amount medium in the first pressure chamber and pressure are applied to the discharge medium in the second pressure chamber. The apparatus has a second pressure applying means for applying the pressure. The first pressure applying means applies a pressure to the quantitation medium in the first pressure chamber, so that the quantitation medium bleeds from a first nozzle communicating therewith. The discharge medium is discharged from the second nozzle communicating with the discharge medium in the second pressure chamber by applying pressure to the discharge medium in the second pressure chamber by the second pressure applying means.

By the way, the first and second pressure applying means expands and contracts by changing the drive voltage to apply pressure to the first pressure chamber and the second pressure chamber. A piezo element for applying a pressure to a fixed amount medium and a discharge medium filled therein may be used. In such a pressure applying means, a quantitative medium which oozes toward the first and second nozzles by the magnitude of the driving voltage, the pulse width, the timing of applying pressure to the first and second pressure chambers, and the like. And the amount of the ejection medium to be ejected is regulated.

The amount of the quantitation medium that oozes out of the first nozzle is specifically adjusted by adjusting the amount by which the first pressure applying means is deformed from the standby state.
In other words, in order to obtain a non-maximum halftone density, the pressure applying means must be stopped before the deformation amount required to exude the maximum quantitative medium amount necessary to obtain the maximum density is reached. After that, the operation of returning to the original standby state is performed again. In other words, the rate of change of the amount of deformation of the pressure applying means is constant irrespective of the amount of the quantifying medium that exudes.

By the way, a force that tends to remain in the first nozzle acts on the quantitative medium due to surface tension or the like. Therefore, when a small amount of the quantitation medium is oozed out to obtain a low concentration, the force to be left in the first nozzle becomes relatively large with respect to the ooze-out force, and The reliable mixing operation to the ejection medium cannot be performed. That is, it is impossible to form dots with an appropriate ink density at a low density.

In view of such circumstances, the present invention ensures that the quantitation medium is mixed with the ejection medium even in the case of low-density printing in which the quantitation medium slightly leaks out.
It is an object of the present invention to provide a driving method of a printer device that enables a reliable mixing and discharging operation from a low density to a high density.

[0017]

In order to achieve the above object, a method of driving a printer apparatus according to the present invention comprises a first pressure chamber into which a fixed amount medium is introduced, and a second pressure chamber into which a discharge medium is introduced.
And a first nozzle communicating with the first pressure chamber and a second nozzle communicating with the second pressure chamber are opened to be adjacent to each other, and Having a first pressure application unit for applying pressure to the quantitation medium in the pressure chamber to extrude the quantification medium and a second pressure application unit for applying pressure to the ejection medium in the second pressure chamber to eject the ejection medium The first pressure applying means of the printer having a head is caused to perform an extruding operation from a steady state, and the quantitative medium is exuded from the first nozzle toward the second nozzle, and the quantitative medium is discharged from the second nozzle. After contacting the ejection medium near the leading end with the ejection medium, the second pressure applying unit performs an ejection operation from a steady state, and ejects the ejection medium from the second nozzle to mix and eject the fixed medium and the ejection medium. In the driving method, the first pressure The ratio of extrusion amount change of the extrusion operation of the pressurizing means, and wherein the changing to become larger as the extrusion rate decreases.

A method for driving a printer device according to the present invention comprises:
As a result, the lower the density to be printed, that is, the smaller the pushing amount, the larger the ratio of the pushing amount change of the first pressure applying means, and the higher the deformation rate of the droplet from the first nozzle. Become. For this reason, even if the density to be printed is low, the force that causes the quantitative medium to seep out from the first nozzle does not become relatively smaller than the force that tends to remain in the first nozzle due to surface tension or the like. Yes. Therefore, it is possible to form dots with an appropriate ink density even at the time of low-density printing, and it is possible to perform a reliable mixed discharge operation from low to high density.

It should be noted that the rate of change in the amount of extrusion in the extrusion operation of the first pressure applying means can be changed even if it is polygonally changed.
The shape may be changed in a curved line, or may be a combination of a polygon and a curved line.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. First, a printer device to which the driving method of the present invention can be applied will be described.
However, here, an example of a print head of a so-called carrier jet type printer device that mixes and discharges ink while mixing the diluting liquid will be described, and an example of a print head having a plurality of nozzle sets will be described. As shown in FIG. 1, the print head mixes and discharges ink and a diluting liquid, and a pressure chamber unit 1 having two pressure chambers and a second pressure chamber unit corresponding to the two pressure chambers.
Of the piezo unit 2 and the first piezo unit 3.

The pressure chamber unit 1 mixes and discharges the ink and the diluting liquid as described above, and as shown in an enlarged view in FIG. 2, a second nozzle 4 having a diluting liquid discharge port therein. A plate-shaped orifice plate 8 in which a second inlet 5 communicating therewith, a first nozzle 6 serving as an ink ejection outlet, and a first inlet 7 communicating therewith are formed substantially at the center. And pressure chamber side walls 9a, 9b, 9 as shown in FIG.
The second pressure chamber 10 is formed by c, 9d, and 9e as partition walls and serves as a diluent flow path, the first pressure chamber 11 serves as an ink flow path, and a vibration plate 12.

In the orifice plate 8, one end of each of the first and second nozzles 6, 4 faces one main surface 8a serving as a printing surface, as shown in an enlarged view in FIG. One end of the first and second inlets 7, 5 communicating with the second nozzles 6, 4 has one end facing the one main surface 8 a.
b. Therefore, the second inlet 5
The second nozzle 4 penetrates the orifice plate 8 as a whole, and the first inlet 7 and the first nozzle 6 also penetrate the orifice plate 8 as a whole. The first and second nozzles 6 and 4 are formed such that the angle between their opening directions indicated by θ in FIG. 2 forms 45 °, and these are formed as a nozzle set.

Furthermore, in the orifice plate 8, as shown in FIG.
4. A second supply chamber 13 having a substantially U-shaped cross section serving as a diluting liquid reservoir and a first supply chamber having a substantially U-shaped cross section serving as an ink reservoir so as to sandwich the first and second introduction ports 7 and 5 therebetween. 14 is formed such that its opening faces the back surface 8b opposite to the one main surface 8a serving as the printing surface.

At this time, pressure chamber side walls 9a, 9b, 9c, 9 are formed as partitions on the back surface 8b side of the orifice plate 8.
d, 9e are laminated, and the pressure chamber side walls 9a, 9b,
The opening of the second supply chamber 13 and the opening of the second inlet 5 are connected by a portion where 9c, 9d, and 9e are not formed, and a second pressure chamber 10 serving as a flow path is formed. A first pressure chamber 11 serving as a flow path is formed by connecting the opening of the first supply chamber 14 and the opening of the first inlet 7.

The pressure chamber side walls 9a, 9b, 9
The diaphragm 12 is formed on the layers c, 9d and 9e, and the first and second pressure chambers 11 and 10 are sealed.

The second piezo unit 2 includes a plate-shaped second laminated piezo element 15 in which a piezoelectric material and a conductive material are alternately laminated, and one end of the second laminated piezo element 15. And a second holder 17 for fixing the second support 16 on which the second laminated piezo element 15 is fixed to the pressure chamber unit 1. The same applies to the first piezo unit 3, in which one end of the first laminated piezo element 18 is fixed to the first support 19, and these are connected to the first holder 2.
0 is fixed to the pressure chamber unit 1.

The first and second laminated piezo elements 18,
15, a piezoelectric material and a conductive material laminated in a direction perpendicular to the longitudinal direction of the first and second pressure chambers 11 and 10;
Alternatively, either one laminated in a direction parallel to the longitudinal direction may be used. The laminated piezo element has a characteristic of extending in the laminating direction when a voltage is applied.

For this reason, the former laminated piezo element expands in the longitudinal direction of the first and second pressure chambers 11 and 10 due to the application of a voltage, and contracts in the direction perpendicular to this. Therefore, this laminated piezo element does not apply pressure to the pressure chamber. Such a laminated piezo element is referred to as d
_This is referred to as a _31- mode laminated piezo element.

On the other hand, in the latter laminated piezo element,
When a voltage is applied, the first and second pressure chambers 11 and 10 extend in a direction orthogonal to the longitudinal direction, and apply pressure to the pressure chambers. Such laminated piezoelectric element is referred to as a laminated piezoelectric element of the d ₃₃ mode.

The second laminated piezo element 15 is disposed so as to face the second pressure chamber 10 via the diaphragm 12, and the first laminated piezo element 18 is also disposed on the diaphragm 12
The first pressure chamber 11 is arranged to face the first pressure chamber 11.

Therefore, in the print head having the above-described configuration, the diluent 21 flows from the diluent tank (not shown) through the supply pipe and the supply groove (not shown) to the second supply chamber 1.
2 from which a second nozzle 4 communicates with a second inlet 5 through a second pressure chamber 10 as shown in FIG.
And a second meniscus D ₂ is formed at the tip of the second nozzle 4 by the diluent 21.

The same applies to one of the inks 22,
The ink is supplied from a not-shown ink tank to a first supply chamber 14 through a supply pipe or a supply groove (not shown), and communicates therefrom through a first pressure chamber 11 to a first inlet 7 as shown in FIG. Then, the first meniscus D ₁ is formed at the tip of the first nozzle 6 by the ink 22.

Further, in this print head,
As described above, a plurality of nozzle sets each including the first nozzle 6 and the second nozzle 4 are arranged adjacent to each other. That is,
As shown in FIG. 3, when viewed from one main surface 8a side of the orifice plate 8 of the print head, a plurality of nozzle sets 30 including the first and second nozzles 6 and 4 are configured such that the second nozzles 4 are connected to each other. Nozzles 6 are arranged adjacent to each other.

FIG. 4 is a cross-sectional view of the print head taken along a line AA ′ in FIG. 3. The orifice plate 8 has a second nozzle 4 connected to the second inlet 5. Are arranged adjacent to each other, and the plurality of second pressure chambers 10 communicated with these are also arranged adjacent to each other. Further, a plurality of second laminated piezo elements 15 facing the plurality of second pressure chambers 10 are also arranged adjacent to each other, one end of which is held by the above-described second support 16, and The body 16 is fixed to a second holder 17.

The print head includes a first supply pipe 32 for supplying, for example, the diluent 21 to the second pressure chamber 10, a first supply pipe 32 and an external diluent tank (not shown). A connecting second supply pipe 23 is also formed. The same configuration is also applied to the first nozzle 6 side of the print head.

Next, FIG. 5 is a cross-sectional view of the orifice plate 8 cut in the vicinity of the first and second pressure chambers 11 and 10, and the second supply chamber 13 is connected to the plurality of second pressure chambers 10. The second pressure chambers 10 are formed in corresponding positions with corresponding sizes, and these second pressure chambers 10 are connected to the second supply chambers 13, respectively. The second supply chamber 13 and the first supply pipe 32 They are connected by a first supply groove 24.

On the other hand, the first supply chamber 14 has a size corresponding to the plurality of first pressure chambers 11 and is formed at a corresponding position. These first pressure chambers 11 correspond to first supply chambers 14.
, And the first supply chamber 14 and the third supply pipe 25 are connected by a second supply groove 26. At this time, the third supply pipe 25 is connected to an external ink tank and the first supply pipe 32 by a fourth supply pipe (not shown).

Next, FIG. 6 shows the print head as viewed from one main surface 8a of the orifice plate 8. For example, the second inlet 5 is formed at the one main surface 8a of the second pressure chamber 10. As shown in FIG.
The second nozzle 4 is communicated through the second pressure chamber 10, and the second laminated piezo element 15 is disposed on the opposite side of the second pressure chamber 10 from the second nozzle 4.

Accordingly, the second liquid from the diluent tank (not shown)
The diluent 2 supplied to the second supply chamber 13 via the supply pipe 23 and the first supply pipe 32 through the first supply groove 24
1 is supplied to each of the plurality of second pressure chambers 10 and is filled in the second nozzle 4 corresponding to each of the second pressure chambers 10 and communicating with the second inlet 5. Then, each second laminated piezo element 15 corresponding to each second pressure chamber 10
Is deformed to pressurize the second pressure chambers 10 respectively,
The diluent 21 is discharged from the second nozzles 4 communicating with the second pressure chambers 10 on the side opposite to the second laminated piezo element 15.

That is, a plurality of second laminated piezo elements 1
5 is deformed and pressurized to the plurality of second pressure chambers 10, the diluent 21 is discharged from the plurality of second nozzles 4 at once, and the selected second laminated piezo element 15 is deformed. Then, the diluent 21 is discharged from the selected second nozzle 4 corresponding to this.

The same is true on the first pressure chamber 11 side, and the first pressure chamber 11 has the first main surface 8a on the first pressure chamber 11 side.
The first nozzle 6 communicates with the first pressure chamber 11 via the inlet 7 of the first pressure chamber 11, and the first laminated piezo element 18 is arranged on the opposite side of the first pressure chamber 11 from the first nozzle 6.

Accordingly, the fourth position from the ink tank (not shown)
The ink 2 supplied to the first supply chamber 14 through the supply pipe 27 and the third supply pipe 25 through the second supply groove 26
2 is supplied to each of the plurality of first pressure chambers 11 and filled in the first nozzles 6 corresponding to the respective first pressure chambers 11 and communicating with the first inlet 7. Then, each first laminated piezo element 18 corresponding to each first pressure chamber 11
Are deformed to pressurize the first pressure chambers 11 respectively,
The ink 22 is ejected from the first nozzles 6 connected to the first pressure chamber 11 on the side opposite to the first laminated piezoelectric element 18.

That is, a plurality of first laminated piezo elements 1
8 are deformed and pressurized to the plurality of first pressure chambers 11, the ink 22 is ejected from the plurality of first nozzles 6 at one time, and the selected first laminated piezo element 18 is deformed. Then, the ink 22 is discharged from the selected first nozzle 6 corresponding to this.

Next, as shown in FIG. 7, the operation of the above-described printer will be described together with a driving voltage waveform in which the maximum driving voltage is 9V. Note that here, the first
And so-called d as the second laminated piezo elements 18 and 15.
_{The case where a 31-} mode laminated piezo element is used will be described.

That is, as shown in FIG. 7A, for example, 9 [V] is applied to the second laminated piezo element 15 in advance at the time of waiting before printing, as shown in FIG. As shown in FIG. 7B, at the time of standby before printing, FIG.
At the time point indicated by, for example, 9 [V] is applied to the first multilayer piezoelectric element 18 in advance.

[0046] Incidentally, at this time, as shown in FIG. 8, the second nozzle opening 4a formed in the orifice plate 8, the second meniscus D ₂ is formed, the first nozzle opening 6a a first meniscus D ₁ is formed.

At the time of printing, based on signals from a head drive, a head feed control, a drum rotation control, and the like provided in the printer device, first, the ink 22 is pushed out from the first nozzle 6 to be exuded. FIG.
7B, the voltage of the first laminated piezo element 18 is gradually reduced to, for example, 0 [V] over 30 [μsec] from the time point indicated by (B) to the time point indicated by (C) in FIG. . Then, the first laminated piezo element 18 gradually expands in the longitudinal direction, and the first pressure chamber 11 is gradually pressurized via the diaphragm 12 as schematically shown in FIG. 6, an ink 22 is applied to the first nozzle opening 6
a to the vicinity of the second nozzle opening 4a,
With the diluent 21 of the nozzle 4.

The pushing operation (driving voltage waveform) from the time point indicated by (B) in FIG. 7B to the time point indicated by (C) in FIG. 7B will be described later in detail.

Also, as shown in FIG.
(B) At the time point shown in (B), the first laminated piezo element 18
7A, the voltage of the second laminated piezo element 15 is applied for 10 [μsec] from the time indicated by (D) in FIG. 7A to the time indicated by (E) in FIG. 7A. And for example 0
Start lowering gradually to [V]. Then, the second laminated piezo element 15 starts to elongate in the longitudinal direction, the second pressure chamber 10 is pressurized via the diaphragm 12, and the internal pressure starts to be applied to the second nozzle 4. Then, as shown in FIG. 10, the diluent 21 is extruded from the second nozzle opening 4 a, and the mixed liquid 40 containing the ink 22 is extruded from the second nozzle 4 in a form pushed by the diluent 21. Then, the ejection operation of the second multilayer piezo element 15 is completed after the operation of pushing out the ink 22 by the first multilayer piezo element 18 is completed.

Then, the voltage of the first laminated piezo element 18 is maintained for 30 [μsec] from the time point indicated by (C) in FIG. 7B to the time point indicated by (F) in FIG. 7B. Also, the voltage of the second laminated piezo element 18 is shown in FIG.
(A) From the point indicated by (E) to the point indicated by (H) in FIG. During this time, a constriction 41 occurs in the mixed solution 40 as shown in FIG. When this state is further continued, FIGS.
As shown in, the mixed solution 40 and the diluent 21 are separated,
The mixed solution 40 is discharged from the second nozzle 4, and the mixed solution 4
0 continues to fly toward the recording material in the form of a sphere, and is recorded on the recording material.

Then, as shown in FIG.
(B) From the time point indicated by (F) in FIG. 7B to the time point indicated by (G) in FIG. 7B, the voltage is gradually returned to the original voltage over 30 [μsec]. Then, the first laminated piezo element 18 starts to contract, and the ink 22 in the first supply chamber 14 is removed from the first pressure chamber 1.
It is taken in 1 and returns to the original state. FIG.
As shown in FIG. 7A, from the time indicated by (H) in FIG. 7A to the time indicated by (J) in FIG. 7A, 30 [μsec]
And gradually return to the original voltage. Then, the second laminated piezo element 15 starts to contract, the diluent 21 in the second supply chamber 13 is taken into the second pressure chamber 10, and returns to the original state.

It should be noted that the first laminated piezo element 18 and the second
When the drive voltage of the laminated piezo element 15 is returned to the original state, the first nozzle 6 is filled with the ink 22 again by the capillary phenomenon, and the diluent 21 is filled again with the second nozzle 4. Then, meniscuses are respectively formed, and the state returns to the state of FIG.

By the way, the driving voltage waveform (hereinafter, referred to as a quantitative waveform) of the first multilayer piezoelectric element 18 from the time point shown in FIG. 7B to the time point shown in FIG. 7C.
Is characterized in that the smaller the operation of the pushing amount of the pushing operation of the first multilayer piezo element 18, the larger the ratio of the change of the pushing amount becomes. That is, as the driving voltage decreases, the driving voltage change rate increases.

Therefore, when the maximum drive voltage is set to 9 V and the drive voltage is set to 9 V, the ink 22 is pushed out from the first nozzle 6 to be exuded and applied to 9 [V] in advance. Then, as shown in FIG. 14, first, 5 [μ] is applied from the time point indicated by (B) in the figure to the time point indicated by (C2) in the figure.
sec] and gradually lower to 6 [V]. Next, from the time point indicated by (C2) in the drawing to the time point indicated by (C1) in the drawing, the voltage is gradually lowered to 3 [V] over 10 [μsec]. Finally, it takes 15 [μs] from the time point indicated by (C1) in the figure to the time point indicated by (C) in the figure to reach 0.
Gradually lower to [V]. This period corresponds to the movement of the printer device between the time point shown in FIG. 7B and the time point shown in FIG.

Next, when the driving voltage becomes 7 [V], the mixed discharge operation is performed according to the following quantitative waveform. In this case, the flow when the driving voltage is 9 [V] is the same up to the point indicated by (C1) in FIG. From the time point indicated by (C1) in FIG. 15 to the time point indicated by (C ′) in the figure, the voltage is gradually lowered to 2 [V] over 5 [μs]. As a result, the time required from the time point indicated by (B) in the figure to the time point indicated by (C ′) in the figure is a total of 20 [μs]. Then, this period corresponds to the movement of the printer device from the time point indicated by (B) in FIG. 7B to the time point indicated by (C) in FIG. Incidentally, FIG. 1 shows the original state.
5 returns to (G) via (F ′) in the figure. This period corresponds to the movement of the printer apparatus from the time point indicated by (C) in FIG. 7B to the time point indicated by (G) in the figure after passing through the time point indicated by (F) in FIG.

It is preferable that the quantitative waveform when the driving voltage is 6 V or more and 9 V or less be the same as the flow when the driving voltage is 7 V.

Next, a quantitative waveform when the driving voltage is 4.5 [V] will be described. In this case, the flow when the driving voltage is 9 [V] is the same up to the time point indicated by (C2) in FIG. From the time point indicated by (C2) in FIG. 16 to the time point indicated by (C ″) in FIG.
Gradually lower to [V]. After all, the time required from the time point indicated by (B) in the figure to the time point indicated by (C ″) in the figure is 10 [μs] in total. And, during this time, FIG.
This corresponds to the movement of the printer device between the time point shown in middle (B) and the time point shown in FIG. By the way, the point (G) in FIG. 16 showing the original state returns through (F ″) in the figure. This period corresponds to the movement of the printer device from the point in time (C) in FIG. 7B to the point in time (G) in FIG.

It is preferable that the quantitative waveform when the drive voltage is 3 [V] or more and 6 [V] or less is the same as the flow when the drive voltage is 4.5 [V].

Finally, a quantitative waveform when the driving voltage is 2.4 [V] will be described. In this case, the flow when the driving voltage is 9 [V] is the same as the flow up to the time point indicated by (C2) in FIG. The time required from the time indicated by (B) in FIG. 17 to the time indicated by (C ′ ″) in the figure is 4
[Μs]. Then, this period corresponds to the movement of the printer device from the time point indicated by (B) in FIG. 7B to the time point indicated by (C) in FIG. Incidentally, the state returns to the point (G) in FIG. 17 showing the original state via (F ″ ′) in the figure. This period corresponds to the movement of the printer device from the point in time (C) in FIG. 7B to the point in time (G) in FIG.

It is preferable that the quantitative waveform when the driving voltage is not less than 0 [V] and not more than 3 [V] is the same as the flow when the driving voltage is 2.4 [V].

The drive voltage V described above and the time t required for the movement corresponding to the movement of the printer from the time shown in FIG. 7B to the time shown in FIG. The relationship is as follows:

T = V / 3 * 50 ≦ V ≦ 3 t = 10 * V / 3−53 ≦ V ≦ 6t = 5 * V−156 ≦ V ≦ 9, where V [V]: drive voltage t [μs]: Time required for the movement corresponding to the movement of the printer device from the time point indicated by (B) in FIG. 7B to the time point indicated by (C) in FIG. That is, V / t = 3/50 ≦ V ≦ 3V / t = (1 + 5 / t) * 0.33 ≦ V ≦ 6V / t = (1 + 15 / t) * 0.26 ≦ V ≦ 9.

As described above, the smaller the driving voltage, the larger the driving voltage change rate V / t. Incidentally, the above-mentioned driving voltages 9 [V], 7 [V], 4.
The drive voltage change rates at 5 [V] and 2.4 [V] are 0.3 [V / μs], 0.35 [V / μs], and 0.
45 [V / μs] and 0.6 [V / μs].

Here, the movement of the ink 22 will be described. The ink 22 tends to exude from the first nozzle 6 by deforming the first laminated piezoelectric element 18. However, at the same time, the ink 22 is also subjected to a force to stay in the first nozzle 6 due to surface tension or the like. The force of the ink 22 to stay in the nozzle 6 does not change so much depending on the amount of the ink 22 to be exuded. In other words, the smaller the amount of the ink 22 that is exuded, the greater the force that causes the ink 22 to stay relatively, and accordingly, the mixing with the diluent 21 discharged from the second nozzle 4 becomes unstable. turn into.

However, if the mixed discharge operation is performed according to the driving voltage waveform as described above, the driving voltage change rate becomes large when the amount of the ink 22 to be exuded is small, and the deformation rate of the first laminated piezoelectric element 18 is increased. Is also larger,
The force to exude also increases. Therefore, even when the amount of the ink 22 to be exuded is small, the force to exude relatively does not become smaller than the force to stay in the first nozzle, so that stable mixed ejection Operation becomes possible.

As described above, in the driving method of the printer device to which the present invention is applied, the driving voltage change rate is increased as the driving voltage is smaller as compared with the operation of pushing out the driving voltage waveform of the first pressure applying means. . Therefore, even if the amount of the quantitation medium to be exuded is small, the deformation rate of the first pressure applying means is large, so that the quantification medium is compared with the force for keeping the quantitation medium in the first nozzle. The force for oozing out is not relatively small.

Therefore, the driving method of the printer according to the present invention can be applied to the printing method of the low density, that is, even if the pushing amount (driving voltage) becomes small, the rate of change of the pushing amount (driving voltage change rate). , The mixing and discharging operation can be reliably performed.

By the way, the driving voltage waveform of the first laminated piezo element 18 in the present invention may be a case where there are only two turning points as shown in FIG.
As shown in FIG. 18, there is no problem even if there is only one turning point. Further, there is no problem even if the number of turning points is three or more as shown in FIG. Further, as shown in FIG. 20, even if a smooth curve is drawn from the time point shown in FIG. 20B to the time point shown in FIG. It goes without saying that there is no problem even in the case of a combination of a polygon and a curve.

The above description has been made on the case where the state where the first multilayer piezoelectric element 18 is pulled is normal. Therefore, in FIG.
This is a case where the state corresponding to the section from (A) to (B) is a steady state.

However, the drive voltage waveform of the present invention is not limited to the case where the state in which the first multilayer piezo element 18 is pulled is steady. The drive voltage waveform of the present invention is applicable even when the state in which the first multilayer piezoelectric element 18 is pressed is steady.

Here, corresponding to FIGS. 14 to 20 described above, quantitative waveforms in which the state in which the first laminated piezoelectric element 18 is pressed are steady are shown in FIGS.

First, FIGS. 21 to 27 show quantitative waveforms in which the state in which the first laminated piezo element 18 is pressed is steady.
14 to 2 showing quantitative waveforms in which the drawn state is steady.
The difference from 0 is that, in FIG. 17 and the like, the steady state is obtained in the sections (G) to (A) and (B), whereas in FIG. 21 and the like, the sections are (C) to (F). Is that it is stationary.

That is, from the time point shown in FIG. 21C to the time point shown in FIG. 24 to the time point shown in FIG. On the other hand, when the pull-in operation of the first multilayer piezo element 18 is completed, the time indicated by (G) in FIG. 21 to FIG. 24, the time indicated by (G ′) in FIG.
The timing indicated by (G ″) in the drawing and the timing indicated by (G ″ ′) in the drawing, and consequently, the start of the push-out operation of the first laminated piezo element 18 is shown in FIGS. The timing shown by B), the timing shown by (B ') in the drawing, the timing shown by (B ") in the drawing, and the timing shown by (B"') in the drawing are different depending on each drive voltage.

Further, FIGS. 21 to 27 showing quantitative waveforms in which the state in which the first laminated piezoelectric element 18 is pressed are steady are shown in FIG. 21 (B) or (B ′) or (B ″) or FIG. The push-out operation of the first multilayer piezo element 18 corresponding to the time point indicated by (C) in the figure from the time point indicated by (B ′ ″)
In FIGS. 14 to 20, which show quantitative waveforms in which the pulled state is steady while the beginning is abrupt and gradually gentle, the push-out operation of the first laminated piezo element 18 is slow and slow at the beginning. Has become steep.

From the time point indicated by (B) in FIG. 21 (C)
This will be described as a representative of the section up to the point indicated by. As in the example described with reference to FIG. 17, for example, the maximum value of the driving voltage is set to 9 V, and the voltage is increased to 9 [V] in advance from the time indicated by (F) to the time indicated by (G) in FIG. It is held until the time point shown in the middle (B). Then, first, 15 [μsec] is applied from the time point indicated by (B) in the figure to the time point indicated by (C2) in the figure to obtain 6
Gradually lower to [V]. Next, from the time point indicated by (C2) in the figure to the time point indicated by (C1) in the figure, 10 [μs
ec] and gradually lower to 3 [V]. Finally, the time is gradually reduced to 0 [V] by applying 5 [μs] from the time point indicated by (C1) in the figure to the time point indicated by (C) in the figure.
This period corresponds to the movement of the printer device between the time point shown in FIG. 7B and the time point shown in FIG. As a result, the push-out operation of the first multilayer piezo element 18 corresponding to the time point indicated by (B) in the drawing and the time point indicated by (C) in the drawing is gentle at the beginning and gradually becomes steep.

FIGS. 21 to 27 show quantitative waveforms in which the state in which the first laminated piezoelectric element 18 is pressed is steady.
FIG. 14 to FIG. 14 show quantitative waveforms in which the drawn state is steady.
This is different from FIG. However, the time required from the time indicated by (B) and (B ') and (B ") and (B"') in FIGS. μs], 20 [μs], 10 [μs],
4 [μs], as in the example described with reference to FIG. 17, the drive voltage change rate increases as the drive voltage decreases.

After all, even if the state in which the first laminated piezoelectric element 18 is pressed is steady, if the amount of the ink 22 to be exuded is small by using the quantitative waveform as in the present invention, the driving voltage change Therefore, the deformation rate of the first laminated piezo element 18 also increases, and the force for exuding the piezoelectric element 18 also increases. Therefore, even when the amount of the ink 22 to be exuded is small, the force to exude relatively does not become smaller than the force to stay in the first nozzle. Will be possible.

Incidentally, similarly to the case where the state where the first multilayer piezoelectric element 18 is pulled is steady, the state where the first multilayer piezoelectric element 18 is pushed is steady.
However, the present invention is not limited to the case where the number of turning points is two. FIG.
There is no problem even if the number of turning points is one as shown in FIG. 5 or three or more as shown in FIG. Further, it goes without saying that there is no problem even in a combination of a polygon and a curve.

[0079]

As is apparent from the above description, the driving method of the printer according to the present invention mixes the quantitative medium extruded by the first pressure means and the discharge medium extruded by the second pressure means. In the method of driving a printer device for ejecting, the rate of change in the amount of extrusion in the pushing operation of the first pressure applying means is changed so as to increase as the amount of extrusion decreases. Since the deformation rate of the droplet from the first nozzle also increases, the force that causes the quantitative medium to seep out from the first nozzle even when the amount of extrusion is small is the force that tends to remain in the first nozzle due to surface tension or the like. It does not need to be relatively small with respect to. Therefore, in the method of driving the printer of the present invention, even if the amount of extrusion is small,
That is, even if the density to be printed is low, it is possible to form dots with an appropriate ink density, and it is possible to perform a reliable mixed discharge operation from low density to high density.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of an essential part showing an example of a print head of a printer to which a method of driving the printer to which the present invention is applied is applicable.

FIG. 2 is an enlarged schematic cross-sectional view of a main part of the vicinity of an orifice plate of an example of a print head of a printer to which a driving method of the printer to which the present invention is applied is applicable.

FIG. 3 is a plan view illustrating an example of a print head of a printer to which a method of driving the printer to which the present invention is applied is applicable.

FIG. 4 is a cross-sectional view illustrating an example of a print head of a printer to which a method of driving the printer to which the present invention is applied is applicable.

FIG. 5 is a sectional view showing an orifice plate as an example of a print head of a printer to which a method of driving the printer to which the present invention is applied is applicable.

FIG. 6 is a plan view schematically illustrating an example of a print head of a printer to which a method of driving the printer to which the present invention is applied is applicable.

FIG. 7 is a diagram illustrating a driving voltage waveform of an example of a driving method of a printer device to which the present invention is applied.

FIG. 8 shows an operation sequence of a print head of a printer device to which a driving method of the printer device to which the present invention is applied can be applied in the order of operation, in which first and second nozzles are provided with first and second nozzles. It is sectional drawing which shows the state in which the meniscus is formed typically.

FIG. 9 shows an operation sequence of a print head of a printer device to which a driving method of the printer device to which the present invention is applied can be applied in an operation order, and shows a state in which ink is mixed with a diluent of a second nozzle. It is sectional drawing which shows typically.

FIG. 10 shows an operation sequence of a print head of a printer device to which a driving method of the printer device to which the present invention is applied can be applied in an operation order, and schematically shows a state in which a mixed solution of a diluent and ink is formed. FIG.

FIG. 11 is a diagram illustrating an operation of the print head of the printer device to which the method of driving the printer device to which the present invention is applied can be applied in the order of printing, and is a cross-sectional view schematically illustrating a state in which the mixed solution is constricted. FIG.

FIG. 12 is a diagram illustrating an operation of a print head of a printer to which a method of driving the printer to which the present invention is applied can be applied in the order of printing, and schematically illustrates a state in which a mixed solution is discharged from a second nozzle. It is sectional drawing shown in FIG.

FIG. 13 is a diagram illustrating an operation of a print head of a printer to which the method of driving the printer to which the present invention is applied can be applied in the order of printing, and schematically illustrates a state in which a mixed solution flies as a spherical droplet. It is sectional drawing shown in FIG.

FIG. 14 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention has been applied.

FIG. 15 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention has been applied.

FIG. 16 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention has been applied.

FIG. 17 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer apparatus to which the present invention has been applied.

FIG. 18 is a diagram illustrating a modified example of a fixed-side drive voltage waveform in a method of driving a printer device to which the present invention is applied.

FIG. 19 is a diagram illustrating a modified example of a fixed-side drive voltage waveform in a method of driving a printer device to which the present invention has been applied.

FIG. 20 is a diagram illustrating a modified example of a fixed-side drive voltage waveform in a method of driving a printer device to which the present invention has been applied.

FIG. 21 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention is applied.

FIG. 22 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention has been applied.

FIG. 23 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention has been applied.

FIG. 24 is a diagram illustrating an example of a change in a fixed-side drive voltage waveform due to a drive voltage in a method of driving a printer device to which the present invention is applied.

FIG. 25 is a diagram showing a modification of the fixed-side drive voltage waveform in the method of driving a printer device to which the present invention is applied.

FIG. 26 is a diagram illustrating a modified example of the fixed-side drive voltage waveform in the method of driving a printer device to which the present invention is applied.

FIG. 27 is a diagram illustrating a modified example of the fixed-side drive voltage waveform in the driving method of the printer device to which the present invention is applied.

[Explanation of symbols]

4 2nd nozzle, 6 1st nozzle, 10 2nd pressure chamber, 11 1st pressure chamber, 15 2nd laminated piezo element, 18 1st laminated piezo element, 21 diluent, 22
ink

Claims (3)

[Claims] 1. A first pressure chamber into which a metering medium is introduced,
A second pressure chamber into which a discharge medium is introduced;
A first nozzle communicating with the first pressure chamber and a second nozzle communicating with the second pressure chamber are opened so as to be adjacent to each other, and a pressure is applied to the fixed amount medium in the first pressure chamber. First pressure application of a printer apparatus having a print head having first pressure application means for extruding a fixed amount medium and second pressure application means for applying pressure to a discharge medium in a second pressure chamber to discharge the discharge medium After the means performs the pushing operation from the steady state, the quantitative medium is oozed from the first nozzle toward the second nozzle, and the quantitative medium is brought into contact with the ejection medium near the tip of the second nozzle. In a driving method of a printer device for causing a second pressure applying unit to perform a discharging operation from a steady state and discharging a discharging medium from a second nozzle to mix and discharge a fixed amount medium and a discharging medium, Extrusion push A method of driving a printer device, wherein the rate of change in the amount of ejection is changed so as to increase as the amount of extrusion decreases. 2. The printer device according to claim 1, wherein the rate of change of the pushing amount of the pushing operation of the first pressure applying means is changed in a polygonal manner so as to increase as the pushing amount decreases. Drive method. 3. The printer apparatus according to claim 1, wherein the ratio of the change in the amount of extrusion in the pushing operation of the first pressure applying means is changed so as to increase as the amount of extrusion decreases. Drive method.