JP3298201B2 - Electroosmotic membrane device and on-demand type ink jet printer using the electroosmotic membrane device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroosmotic membrane device which allows ink to permeate by an electroosmotic action while a driving voltage pulse is supplied, and quantifies ink using the electroosmotic membrane device. On-demand type inkjet printer device that intermittently ejects the mixed ink and the ink solution in the mixing section, particularly,
By using an electroosmotic membrane device for improving the responsiveness by the drive voltage pulse for accurate and high-speed quantification of the ink and an electroosmotic membrane device for accurate quantification of the ink, the mixing is improved. The present invention relates to an on-demand type ink jet printer device which makes the concentration of a mixed liquid formed in a printing section more accurate and increases the printing speed.

[0002]

2. Description of the Related Art Conventionally, ink and an ink solution are mixed,
There is known an on-demand type ink jet printer which discharges the mixed liquid intermittently.

[0003] In this on-demand type ink jet printer device, as shown in FIG. 13, for example, a head section 100 is provided with a pressure transmission chamber 101 to which the ink solution is supplied via an ink solution supply path 106, and an ink supply chamber 101. Road 1
07, an ink quantification unit 102 for quantifying and discharging the ink supplied through an ink supply line 07, an electrostrictive vibrator 103 for applying pressure to the pressure transmission chamber according to print data, and a quantification unit for the ink quantification unit 102. The mixing unit 104 includes a mixing unit 104 that mixes the converted ink and the ink solution to form a mixed liquid, and a discharge port (orifice) 105 that discharges the mixed liquid.

The ink quantifying unit 102 is a conventional electroosmotic membrane device, in which a porous membrane 102a is sandwiched between first and second mesh electrodes 102b and 102c. The first mesh electrode 102b is grounded, and the second mesh electrode 102c is connected to an input terminal 108 to which a driving voltage pulse is supplied.

The electrostrictive vibrator 103 is a so-called single plate PZT in which a piezoelectric ceramic 103a is sandwiched between a pair of electrodes 103b, and is provided adjacent to the pressure transmission chamber 101.

In a conventional on-demand type ink jet printer having the head unit 100 having such a configuration, when printing is started, a first pulse shown in FIG. 15 is synchronized with a timing pulse from a control circuit (not shown). The first pulse is output from the pulse generation circuit 120, and the second pulse is output from the second pulse generation circuit 121 in synchronization with the first pulse. The first and second pulses are supplied to an amplifier 122 and added to each other, and the gain thereof is amplified. As a result, the drive voltage pulse is supplied to the output terminal 123 and the input quantification unit 108 shown in FIG. The second mesh electrode 102c is supplied to the second mesh electrode 102c.

The control circuit controls the PZT drive waveform generation circuit 124 so as to output a PZT drive voltage pulse in synchronization with the generation of the first and second pulses. The above P output from the PZT drive waveform generation circuit 124
The ZT drive voltage pulse has its gain amplified by the amplifier 125 and is supplied to the electrode 103b of the electrostrictive vibrator 103 shown in FIG.

More specifically, every time printing is performed, the second mesh electrode 102c of the ink quantification unit 102
4 (a), time t50 to time t51, time t
The driving voltage pulse, which is a repetitive waveform of a predetermined voltage that goes to a high level during a period from 52 to time t53, from time t54 to time t55, is supplied, and the first mesh electrode 1 is turned on.
Since 02b is grounded as described above, the voltage value of the first mesh electrode 102b becomes zero as shown in FIG.

The ink quantification unit 102 is supplied through the ink supply path 107 and stored in the first ink chamber 109 by the so-called electroosmosis phenomenon every time the high-level drive voltage pulse is supplied. The ink is transmitted through the second ink chamber 110. That is, FIG.
At time t50 to time t51, and time t52 to time t, during which the high-level drive voltage pulse is supplied.
During the time t53, the time t54 to the time t55,...
The first ink chamber 109 to the second ink chamber 11
Time t51 to time t52 and time t5 between the time when the ink is supplied to 0 and the low-level drive voltage pulse is supplied.
From 3 to time t54, from time t55 to time t56,..., The electro-osmotic phenomenon does not occur in the ink quantification unit 102, and no ink is supplied from the first ink chamber 109 to the second ink chamber 110. . The ink supplied to the second ink chamber 110 is supplied to the mixing unit 104 via an ink supply path 111.

The amount of the ink transmitted can be varied by varying the application time of the high-level drive voltage pulse. Therefore, by varying the application time of the high-level drive voltage pulse, the print density can be varied.

The mixing section 104 includes the pressure transmitting chamber 1
01 is supplied. Therefore, when the ink is supplied through the ink supply path 111, the ink and the ink solution are mixed in the mixing section 104, and a mixed liquid is formed.
As described above, the amount of the ink from the ink quantification unit 102 is an amount corresponding to the print density. Therefore, the mixed liquid becomes a mixed liquid having a desired print density.

On the other hand, the electrostrictive vibrator 103 includes the PZ
It bends every time a T drive voltage pulse is supplied. As described above, the ink solution is supplied to and accumulated in the pressure transmission chamber 101 via the ink solution supply passage 106. Therefore, when the electrostrictive vibrator 103 bends, pressure is applied to the pressure transmission chamber 101 and the pressure transmission chamber 10
1 is extruded toward the mixing unit 104 side. Therefore, with the bending of the electrostrictive vibrator 103, the mixed liquid formed in the mixing section 104 is discharged through the orifice 105 and is sprayed on the recording paper. Thereby, desired characters, figures, and the like can be printed on the recording paper.

As described above, the conventional on-demand type ink jet printer can form an ink (mixed liquid) having a desired concentration by mixing the ink and the ink solution. By varying the amount, the density gradation of a character or the like to be printed can be set freely.

[0014]

However, the above-mentioned conventional on-demand type ink-jet printer apparatus has the above-described ink quantification unit 102 which is a conventional electroosmotic membrane apparatus.
The driving is performed by a driving voltage pulse having a repetitive waveform of a predetermined voltage as shown in FIG. 14A, but at times t51, t53, t55, t57. Also, the movement of the ink is caused by the inertia of the ink flow, the movement and vibration of the mesh electrode and the porous film due to the ink flow, and the discharge effect of the inter-electrode capacitor for forming the drive voltage pulse of the predetermined voltage. I was If the movement of the ink occurs even at the electroosmotic end time, the amount of ink supplied to the mixing unit 104 becomes larger than a desired amount, and the print density becomes higher than the intended density. This causes inconvenience.

Further, in the conventional on-demand type ink jet printer, the response of the ink quantification unit 102 to the electroosmosis phenomenon is poor due to the above-mentioned causes. For this reason, there has been a problem in increasing the printing speed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an electroosmotic membrane device capable of accurately and rapidly quantifying and transmitting ink. It is an object of the present invention to provide an on-demand type ink jet printer capable of achieving accurate print density and high printing speed by providing the apparatus.

[0017]

[0018]

The electroosmotic membrane device according to the present invention comprises first and second two-layer porous membranes which allow liquid to permeate in a direction corresponding to the direction of an applied electric field. Third three
An electroosmotic portion alternately interposed between a plurality of mesh electrodes; a pulse applying means for applying a drive voltage pulse between the first, third, and second mesh electrodes; 1, the pulse applying means is controlled so that a driving voltage pulse of a predetermined polarity is applied between one electrode between a third mesh electrode and the second mesh electrode, and the electroosmotic portion is set in a transparent state. Further, the pulse applying means is controlled so that driving voltage pulses of the same polarity are respectively applied between the first and third mesh electrodes and the second mesh electrode to dynamically stop the electroosmotic section. The above-mentioned subject is solved by having control means for setting a state.

Further, in the electroosmosis membrane device according to the present invention, the control means may be configured so that the direction of the electric field between the first and third mesh electrodes and the second mesh electrode is the second direction.
The driving voltage pulse in the direction of the mesh electrode of
By controlling the pulse applying means so as to be applied between the respective electrodes, the above-described problem is solved by setting the electroosmotic unit to the dynamic stationary state.

Alternatively, the on-demand type ink jet printer according to the present invention pressurizes the first liquid in the pressure transmission chamber, and the first liquid is mixed by the mixing section provided near the discharge port of the pressure transmission chamber. An on-demand type ink jet printer device having a head unit for intermittently mixing and discharging a second liquid separately supplied, wherein the liquid is applied in a direction corresponding to the direction of an applied electric field. An electro-osmotic unit comprising a porous membrane to be permeated sandwiched between the first and second mesh electrodes;
Pulse applying means for applying a driving voltage pulse between the mesh electrodes of the electroosmotic section, and controlling the pulse applying means so that a driving voltage pulse of a predetermined polarity is applied between the mesh electrodes of the electroosmotic section. Controlling the pulse applying means such that after applying the driving voltage pulse having the predetermined polarity, a driving voltage pulse having a polarity opposite to the driving voltage pulse having the predetermined polarity is applied between the mesh electrodes for a predetermined time. The above problem is solved by including a control unit.

Further, the on-demand type ink jet printer according to the present invention pressurizes the first liquid in the pressure transmission chamber, and the first liquid is mixed in the mixing section provided near the discharge port of the pressure transmission chamber. An on-demand type ink jet printer device having a head unit for intermittently discharging a mixture of a liquid and a separately supplied second liquid, wherein the liquid permeates in a direction corresponding to a direction of an applied electric field. An electroosmotic portion, in which first and second two-layered porous membranes are alternately sandwiched between first to third three mesh electrodes, the first and third mesh electrodes and the second Pulse applying means for applying a driving voltage pulse between the mesh electrodes,
Controlling the pulse applying means so that a driving voltage pulse of a predetermined polarity is applied between one electrode between a third mesh electrode and the second mesh electrode to make the electroosmotic portion in a transmissive state; Controlling the pulse applying means so that driving voltage pulses of the same polarity are respectively applied between the first and third mesh electrodes and the second mesh electrode to bring the electroosmotic unit into a dynamic stationary state. The above-mentioned subject is solved by having the control means which performs.

Further, the on-demand type ink jet printer according to the present invention solves the above-mentioned problem, characterized in that the first liquid is a transparent solvent and the second liquid is an ink.

[0023]

According to the electroosmotic membrane device of the present invention, the mesh of the electroosmotic portion is formed by sandwiching a porous membrane that allows liquid to permeate in a direction corresponding to the direction of an applied electric field between first and second mesh electrodes. An electroosmosis membrane device that allows a liquid to permeate by applying a driving voltage pulse from a pulse applying unit between electrodes, wherein the control unit controls the driving unit to generate a driving voltage pulse having a predetermined polarity between mesh electrodes of the electroosmotic unit. While controlling the pulse applying means so as to be applied, after applying the drive voltage pulse of the predetermined polarity, a drive voltage pulse having a polarity opposite to the drive voltage pulse of the predetermined polarity is applied to the mesh electrode for a predetermined time. The pulse applying means is controlled so as to be applied.

Thus, immediately after the completion of the permeation of the liquid,
The force (braking force) in the direction opposite to the direction in which the liquid is transmitted by the drive voltage pulse having the opposite polarity acts, and it is possible to prevent the flow of the liquid unnecessarily.

Further, the electroosmotic membrane device according to the present invention has a first liquid permeating liquid in a direction corresponding to the direction of the applied electric field.
And the first and third mesh electrodes of the electroosmotic portion, in which the second two-layer porous membrane is alternately sandwiched between the first to third three mesh electrodes, and the second mesh electrode An electroosmosis membrane device that transmits a liquid by applying a driving voltage pulse from a pulse applying unit between the first and third mesh electrodes and the second mesh electrode. The pulse applying means is controlled so that a driving voltage pulse of a predetermined polarity is applied between one of the electrodes, so that the electroosmotic portion is in a transmissive state, and the first and third mesh electrodes are connected to the second and third mesh electrodes. The pulse applying means is controlled so as to apply a driving voltage pulse of the same polarity between the mesh electrodes, and the electroosmotic unit is brought into a dynamic stationary state.

More specifically, the control means includes the first and second control means.
The driving voltage pulse is applied so that the direction of the electric field between the third mesh electrode and the second mesh electrode is in the direction of the second mesh electrode, respectively. By controlling the application means, the electroosmotic unit is brought into the dynamic stationary state. Accordingly, an electric field having a polarity opposite to the direction in which the liquid permeates is formed between one of the electrodes, and the braking force acts to prevent unnecessary flow of the liquid. .

On the other hand, the on-demand type ink jet printer according to the present invention pressurizes the transparent solvent, which is the first liquid, in the pressure transmission chamber, and uses a mixing section provided near the discharge port of the pressure transmission chamber. An on-demand type ink jet printer having a head unit for intermittently discharging the transparent solvent and an ink which is a second liquid separately supplied, wherein the control unit controls an applied electric field. The first and second porous films that allow the ink liquid to pass therethrough in a direction corresponding to the direction
The pulse applying means was controlled so that a driving voltage pulse of a predetermined polarity was applied between the mesh electrodes of the electroosmotic portion sandwiched between the second mesh electrodes, and the driving voltage pulse of the predetermined polarity was applied. Then, the pulse applying means is controlled so that a driving voltage pulse having a polarity opposite to the predetermined polarity is applied to the mesh electrode for a predetermined time.

As a result, immediately after the completion of the transmission of the ink, a force (braking force) in a direction opposite to the direction in which the ink liquid is transmitted by the driving voltage pulse of the opposite polarity acts, and the useless flow of the ink is prevented. Can be blocked. For this reason,
In the mixing section, a mixed solution having an accurate concentration can be quickly formed.

Further, the on-demand type ink jet printer according to the present invention pressurizes the transparent liquid as the first liquid in the pressure transmission chamber, and a mixing section provided near the discharge port of the pressure transmission chamber includes: An on-demand type ink jet printer having a head unit for intermittently discharging the transparent solvent and an ink which is a second liquid separately supplied, wherein the control unit controls an applied electric field. The first and second electro-osmotic portions of the first and second two-layer porous membranes, which allow ink to pass through in a direction corresponding to the direction, are alternately sandwiched between first to third three mesh electrodes. 3) controlling the pulse applying means so that a driving voltage pulse of a predetermined polarity is applied between one of the electrodes between the third mesh electrode and the second mesh electrode to make the electroosmotic portion in a transmission state; In addition, the first and third menus Respectively between the shoe electrode and said second mesh electrode by controlling the pulse applying means so that the driving voltage pulse of the same polarity is applied to the dynamic stationary state the electroosmotic unit.

As a result, an electric field having a polarity opposite to the direction in which the ink passes through is formed between one of the electrodes, and the braking force acts to prevent wasteful ink flow. be able to. Therefore, a mixed solution having an accurate concentration can be quickly formed in the mixing section.

[0031]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an electroosmosis membrane device according to the present invention and an on-demand type ink jet printer using the electroosmosis membrane device will be described below in detail with reference to the drawings.

First, the electroosmotic membrane device according to the present invention can be provided in an on-demand type ink jet printer device, for example, as shown in FIG.

That is, in FIG. 1, the head unit 1 of the on-demand type ink jet printer according to the first embodiment is supplied with the ink as the first liquid, and quantifies and discharges the ink. Ink quantification unit 2 which is an electroosmosis membrane device according to the first embodiment of the present invention
A pressure transmitting chamber 3 to which a transparent solvent (ink solution) as a second liquid is supplied, an electrostrictive vibrator 4 for transmitting pressure to the pressure transmitting chamber 3, and an ink solution from the pressure transmitting chamber 3. And a mixing nozzle 5 which is a mixing unit that mixes the ink from the ink quantification unit 2 to form a mixed liquid and discharges the mixture.

The tip of the mixing nozzle 5 (the side not connected to the pressure transmitting chamber 3) is a discharge port (orifice) 6 for discharging the mixed liquid.

As shown in FIG. 2, the ink quantification unit 2 divides one porous film 10 into the first and second mesh electrodes 1.
The ink chamber in the ink quantification unit 2 is partitioned into first and second two ink chambers 14 and 15 by an electroosmotic unit 13 sandwiched between the first and second ink chambers 1 and 12. The first
The ink chamber 14 is connected to an ink reservoir (not shown) for supplying ink based on print data via a first ink supply path 16.
Is connected to the mixing nozzle 5 via a second ink supply path 17.

The first mesh electrode 11 is connected to an input terminal 18 to which a drive voltage pulse formed based on print density designation data described later is supplied. Is grounded.

The pressure transmission chamber 3 is connected via an ink solution supply path 7 to an ink solution storage chamber (not shown) for supplying an ink solution based on print data.

The electrostrictive vibrator 4 includes a piezoelectric ceramic 4
a sandwiched between a pair of electrodes 4b, a so-called single plate P
ZT, which is provided adjacent to the back side of the pressure transmission chamber 3.

The head portion 1 has an outer surface formed by an orifice plate 8 having an inner surface shape enclosing the ink quantifying portion 2, the pressure transmission chamber 3 and the electrostrictive vibrator 4, and an outer surface shape substantially cubic. Are formed.

As shown in FIG. 3, the on-demand type ink jet printer according to the first embodiment as a whole is externally connected to the head 1 having the above-described configuration and the input terminal 25. A memory (line buffer memory or frame memory, etc.) 26 for temporarily storing print data, which is data corresponding to the supplied characters and figures to be printed, as necessary, a gamma correction of the print data, In the case of the above, a correction circuit 27 that performs color correction, and when the head unit 1 has a multi-orifice configuration, corrects a printing capability that varies for each orifice, a driver 28 that drives the head unit 1, The head part 1
A control system 29 for controlling the driving of a motor for moving the paper and a motor for winding the recording paper; and the head unit 1 and the memory 2 based on the print data supplied from the outside.
6, a correction circuit 27, a driver 28, and a control circuit 30 for controlling a control system 29.

Next, the operation of the on-demand type ink jet printer according to the first embodiment having such a configuration will be described.

First, when printing is started, print data written on a floppy disk or the like is read out by, for example, a document creating device (a so-called word processor), and this print data is input via the input terminal 25 shown in FIG. Is supplied to the control circuit 30.

The order of printing differs depending on the configuration of the head unit 1 and the printing unit, and also has a relationship with the order of inputting print data.
6, the print data is once written, read, and supplied to the driver 28 and the like. In some cases, the print data needs to be corrected. Therefore, the correction circuit 27 stores data (temperature, input signal, etc.) for correcting the printing capability of the head unit 1 and data (γ correction, color correction, etc.) for correcting the printing data in the ROM. The control circuit 30 corrects the print data based on the respective data, and supplies the corrected print data to the driver 28 and the like.

The control circuit 30 supplies the print data to the ink solution storage chamber and the ink storage chamber (not shown) provided in the head unit 1. When the print data is supplied to the ink solution reservoir, the ink solution is supplied to the pressure transmission chamber 3 via the ink solution supply path 7. When the print data is supplied, the ink reservoir supplies the ink to the first ink supply path 1.
6, the first ink chamber 14 of the ink quantification unit 2
To supply.

It should be noted that the print data also includes print density designation data which is data for designating print density. For this reason, the control circuit 30 extracts the print density designation data from the print data and, based on the print density designation data, as shown in FIG. During the time t6, a drive voltage pulse having a positive polarity high level is formed and supplied to the head unit 1, and a predetermined drive voltage after the supply of the drive voltage pulse having a positive polarity high level is completed. A drive voltage pulse having a negative low level is formed between time t2 and time t3, between time t6 and time t7, which is the time, and is supplied to the head unit 1. The driving voltage pulse supplied to the head unit 1 is supplied to the first mesh electrode 11 of the electroosmotic unit 13 via the input terminal 18 shown in FIG.

The electroosmotic membrane section 13 is provided in the same manner as in FIG.
, Between time t1 and time t2, and between time t5 and time t6
When a high-level driving voltage pulse of positive polarity is supplied to the first mesh electrode 11 during the period..., The direction of the electric field is changed to the direction A in FIG. 2 (from the first ink chamber 14 to the second ink , A so-called electroosmosis phenomenon). Thus, the ink in the first ink chamber 14 permeates into the second ink chamber 15. The supply time and voltage value of the high-level drive voltage pulse of the positive polarity are variable according to the designated print density.

Next, the electroosmotic section 13 is
When the low-level drive voltage pulse of the negative polarity is supplied between time t2 and time t3, between time t6 and time t7 shown in (b), the direction of the electric field is changed to the direction B in FIG. (The direction from the second ink chamber 15 to the first ink chamber 14), and a braking force is generated. Therefore, the ink flow due to inertia or the like generated after the supply of the positive polarity high-level driving voltage pulse is prevented by the braking force due to the negative polarity low-level driving voltage pulse.

Thus, it is possible to prevent the useless flow of the ink due to the inertia or the like, to make the movement amount of the ink accurate (the ink can be accurately quantified), and to respond to the electroosmosis phenomenon. Can be speeded up.

The supply time and voltage value of the low-level drive voltage pulse are determined by the capacity of the first ink chamber 14, the inner diameter of the ink supply path 16, the amount of ink movement, the speed of ink movement, and the like. Is done.

Next, the ink flowing into the second ink chamber 15 is supplied to the mixing nozzle 5 through the ink supply path 17. The mixing nozzle 15 is supplied with the ink solution from the pressure transmission chamber 3. For this reason,
When the ink is supplied, the ink is mixed with the ink solution, and a mixed liquid is formed in the mixing nozzle 5.

As described above, the ink supplied to the mixing nozzle 5 is accurately quantified. Therefore, the mixed liquid formed in the mixing nozzle 5 is
The density is accurate based on the print density designation data. Further, since the ink to be quantified to be supplied to the mixing nozzle 5 can be quickly formed, the constant concentration mixed liquid can be quickly formed.

On the other hand, the driver 28 shown in FIG.
When the drive data is supplied from the control circuit 30, the drive data is set to a high level from time t3 to time t4, time t7 to time t8... As shown in FIG. Is formed, and this print trigger is supplied to the electrode 4b of the electrostrictive vibrator 4 of the head unit 1 shown in FIG. The time when the print trigger is at the high level is the time for performing printing, and the electrostrictive vibrator 4 bends when the high-level print trigger is supplied. Thereby, the pressure due to the bending of the electrostrictive vibrator 4 is transmitted to the pressure transmission chamber 3, the volume in the pressure transmission chamber 3 changes, and the mixed liquid formed by the mixing nozzle 5 moves the orifice 6 through the orifice 6. Printing is performed by spraying the recording paper on the recording paper.

The electrostrictive vibrator 4 and the electroosmotic part 1
The control of No. 3 may be described below. In this case, the second mesh electrode 12 of the electroosmotic section 13
Is connected to an input terminal to which a second pulse described below is supplied without being grounded.

That is, based on the print density designation data from the control circuit 30, the first pulse generation circuit 31 shown in FIG.
, A high-level first pulse is formed between time t14 and time t15..., And the second pulse generation circuit 32 shown in FIG.
2 and between the time t15 and the time t16, a second pulse which becomes high level is formed, and the PZT drive waveform generation circuit 33 shown in FIG.
12 to time t13, time t16 to time t17 ...
A high-level print trigger is formed. Then, the first pulse is amplified by the amplifier 34 and supplied to the first mesh electrode 11 of the electroosmotic unit 13 through the output terminal 37, and the second pulse is amplified by the amplifier 35 and output to the output terminal 37. The print trigger is amplified by an amplifier 36 and supplied to an electrode 4b of the electrostrictive vibrator 4 via an output terminal 39, while being supplied to the second mesh electrode 12 via 38.

As a result, the time t shown in FIG.
10 to time t11, time t14 to time t15 ...
Since the first pulse at a high level is supplied to the first mesh electrode 11, the arrow A shown in FIG.
An electric field in the direction is generated, and the ink flows from the first ink chamber 14 to the second ink chamber 15. In addition, between time t11 and time t12 shown in FIG. 6C, which is a predetermined time after the supply of the high-level first pulse,
Between time t15 and time t16, the high-level second pulse is supplied to the second mesh electrode 12, so that an electric field in the direction of arrow B shown in FIG. 2 is generated. . Thus, the above-described braking force acts to prevent the flow of the ink. Accordingly, the accurately quantified ink as described above can be quickly formed and supplied to the mixing nozzle 5, and a mixed solution having an accurate concentration can be quickly formed.

The mixed liquid is supplied to the orifice 6 by a high-level print trigger supplied to the electrostrictive vibrator 4 between time t12 and time t13 and between time t16 and time t17 shown in FIG. Sprayed onto the recording paper. Thereby, printing with a desired print density can be performed.

Here, the on-demand type ink jet printer according to the present embodiment has, for example, an appearance as shown in FIG. 7A, and is controlled by the control circuit 30 via the input terminal 40 from the control circuit 30. When the drive data is supplied to the control unit 29, the control system 29 controls the head unit 1 to move to a position where the first character is recorded. Then, together with the printing, the motor provided on the small drum 42 is drive-controlled so that the small drum 42 rotates counterclockwise, for example. The small drum 42 is connected to a drum 44 via a belt 43. For this reason, the drum 42
It rotates together with the rotation of the small drum 42 to feed the recording paper 41 in the vertical direction. When the recording of one line of characters in the vertical direction is completed, the control system 29 controls the head 1 so as to move the head 1 to the recording position of the next line. Thus, the head unit 1 moves to the recording position of the next row along the moving axis 45. The on-demand type ink jet printer device according to the present embodiment is
Printing is performed line by line.

As described above, in the on-demand type ink jet printer according to the present invention, a mixed solution having an accurate concentration can be quickly formed in the mixing nozzle 5. For this reason, it is possible to perform printing at an accurate density designated by the print density designation data,
This can contribute to a higher printing speed.

In the description of the first embodiment, the on-demand type ink-jet printer according to the present invention is designed to print one line at a time. As shown in (b), printing may be performed line by line.

That is, in FIG. 7B, when drive data from the control circuit 30 is supplied to the control system 29 via the input terminal 50, the control system 29 prints the head unit 1 together with printing. Is controlled to move laterally along the movement axis 55. Thus, one line of printing can be performed on the recording paper 51. Next, the control circuit 3
0 indicates that the printing on the recording paper 51 is completed when the printing for one line is completed.
The small roller 53 connected to the drum 52 is rotationally driven so as to move upward by a predetermined amount, and the head unit 1 is controlled to move laterally along the moving shaft 55. Thereby, the next one line can be printed on the recording paper 51.

The on-demand type ink jet printer according to the present embodiment may perform printing on a line-by-line basis.

The head may be a so-called multi-orifice in which a plurality of orifices are continuously provided on a straight line as shown in FIG.

That is, in the on-demand type ink jet printer shown in FIG. 8, the control system 71 drives the head unit 60 according to the drive data supplied through the input terminal 70. The head section 60 is provided with a plurality of orifices so that one line of printing can be performed by one drive. When the printing of one line is completed, the control system 71 controls the rotation of the small roller 73 connected to the drum 72 to move the recording paper 74 upward by one line. Then, the head unit 60 is driven again according to the print data. This makes it possible to print one line at a time on the recording paper.

The on-demand type ink jet printer according to this embodiment may have such a multi-orifice head.

Next, a description will be given of a second embodiment of the on-demand type ink jet printer according to the present invention. In the on-demand type ink jet printer according to the second embodiment, an ink quantification unit 80 as shown in FIG. 9 is provided as ink quantification means. That is, the ink quantification unit 80 is also the second embodiment of the electroosmotic membrane device according to the present invention. The other configuration is the same as the first configuration described above.
This is the same as the configuration of the on-demand type ink jet printer device according to the embodiment. Therefore, the description thereof will be made using the same reference numerals as those of the on-demand type ink jet printer according to the first embodiment.

In FIG. 9, the ink quantification unit 80
Is used to form the first and second two-layer porous membranes 91 and 92 into first to first layers.
The ink chamber in the ink quantifying unit 80 is partitioned into first and second two ink chambers 85 and 86 by the electroosmotic unit 84 interposed between the third three mesh electrodes 81 to 83 alternately. It has become. The first ink chamber 85
Are connected via a first ink supply path 87 to an ink reservoir (not shown) for supplying ink based on print data, and the second ink chamber 86 is connected to the mixing nozzle shown in FIG. 5 and a second ink supply path 88.

The first mesh electrode 81 is connected to an input terminal 90 to which a first pulse, which will be described later, is supplied. The second mesh electrode 82 is grounded. The mesh electrode 83 is connected to an input terminal 89 to which a second pulse described later is supplied.

Next, the ink quantification unit 8 having such a configuration will be described.
The operation of the on-demand type inkjet printer device according to the second embodiment having 0 will be described.

First, when print data is supplied to the control circuit 30 shown in FIG. 3, the control circuit 30
During the printing of one line, for example, between the time t20 and the time t27 shown in (d), a high-level second pulse is formed, and this is output to the third pulse via the input terminal 89 shown in FIG. To the mesh electrode 83. In addition, during the printing of one line, the control circuit 30 controls the time from the time when one character (dot) is printed to the time when the next character (dot) is printed, from time t20 to time t20 in FIG. t21
, A high-level first pulse as shown at time t22 to time t24... Is supplied to the first mesh electrode 81 via the input terminal 90 shown in FIG. As described above, the second mesh electrode 82 is grounded, and its voltage value is always zero as shown in FIG. For this reason, the second mesh electrode 81 and the second mesh electrode 82
An electric field is generated in the direction from the second ink electrode 86 to the first ink chamber 85, and the first ink chamber 8 is disposed between the second mesh electrode 82 and the third mesh electrode 83.
5 generates an electric field in a direction from the second ink chamber 86 to the second ink chamber 86. Therefore, although the ink accumulated in the first ink chamber 85 is transmitted through the second porous film 92 as shown in FIG. 11, the reverse electroosmosis phenomenon occurring in the first porous film 91 is caused. As a result, the first porous membrane 91 does not permeate due to the braking force, and its flow is blocked (dynamically stationary state).

Next, during the printing of one character (dot), the control circuit 30 operates between time t21 and time t22, time t24 and time t2 shown in FIG.
During 5, a low-level second pulse is formed and supplied to the first mesh electrode 81 via the input terminal 90. As a result, as shown in FIG. 12, an electric field is not generated between the first and second mesh electrodes 81 and 82 in the direction from the second ink chamber 86 to the first ink chamber 85. For this reason, the braking force of the first porous film 91 is lost, and as shown by the solid arrow and the dotted arrow in FIG.
5 penetrates through the second porous film 92 and the first porous film 91 and passes through the second ink chamber 86.
(Transmission state).

When the control circuit 30 transmits the ink, the control circuit 30 sets the electroosmotic section 84 to the above-described transmission state,
When the ink is not transmitted, the electroosmotic portion 84 is used.
Is the dynamic stationary state described above. This makes it possible to prevent the useless ink flow due to inertia or the like after the transmission state by the dynamic stationary state, and to accurately and accurately quantify the ink in the same manner as in the first embodiment. can do.

The ink supplied to the second ink chamber 86 is supplied to the mixing nozzle 5 shown in FIG. 1 and mixed with the ink solution to form a mixed liquid as described above.

Then, the control circuit 30 determines whether the mixed liquid has been formed in the mixing nozzle 5 in FIG.
Between time t23 and time t24 shown in FIG.
During the period from 6 to time t27, the driver 28 is controlled so that a print trigger is supplied from the driver 28 to the electrostrictive vibrator 4.

As a result, the time t23 to time t24
During the period between time t26 and time t27,.
The mixed liquid is discharged from the orifice 6 shown in FIG.

As described above, the on-demand type ink jet printer according to the second embodiment can also quickly form a mixture having an accurate concentration. Therefore, it is possible to contribute to an increase in printing speed.

[0076]

[0077]

According to the electroosmotic membrane device of the present invention, the first and second two-layer porous membranes that allow the liquid to permeate in the direction corresponding to the direction of the applied electric field are used. The liquid is applied by applying a driving voltage pulse from a pulse applying means between the first and third mesh electrodes and the second mesh electrode of the electroosmotic portion sandwiched between two mesh electrodes alternately. An electroosmotic membrane device for transmitting light, wherein the control means applies a drive voltage pulse having a predetermined polarity between one of the first and third mesh electrodes and the second mesh electrode. The pulse applying means is controlled so that the electroosmotic portion is in a transmissive state, and a driving voltage pulse of the same polarity is applied between the first and third mesh electrodes and the second mesh electrode. That is, the first and third messages The pulse applying means so that drive voltage pulses are applied between the electrodes so that the direction of the electric field between the mesh electrode and the second mesh electrode is in the direction of the second mesh electrode, respectively. By controlling the electroosmotic unit to the dynamic stationary state,
In the dynamic stationary state, an electric field having a polarity opposite to the direction in which the liquid permeates is formed between one of the electrodes, and the braking force acts to prevent unnecessary flow of the liquid. be able to. Therefore, the response speed of the electroosmosis phenomenon can be increased, and the liquid can be accurately quantified and permeated.

On the other hand, in the on-demand type ink jet printer according to the present invention, the transparent solvent as the first liquid is pressurized in the pressure transmission chamber, and the mixing section provided near the discharge port of the pressure transmission chamber is An on-demand type ink jet printer having a head unit for intermittently discharging the transparent solvent and an ink which is a second liquid separately supplied, wherein the control unit controls an applied electric field. The first and second porous films that allow the ink liquid to pass therethrough in a direction corresponding to the direction
The pulse applying means was controlled so that a driving voltage pulse of a predetermined polarity was applied between the mesh electrodes of the electroosmotic portion sandwiched between the second mesh electrodes, and the driving voltage pulse of the predetermined polarity was applied. Then, the pulse applying means is controlled so that a driving voltage pulse having a polarity opposite to the predetermined polarity is applied to the mesh electrode for a predetermined time.

As a result, immediately after the completion of the ink transmission, a force (braking force) in the direction opposite to the direction in which the ink liquid is transmitted by the driving voltage pulse of the opposite polarity acts by the driving voltage pulse of the opposite polarity, and the useless ink flow is prevented. Can be blocked. Further, the response speed of the electroosmosis phenomenon can be increased, and the ink can be accurately quantified and supplied to the mixing section. Therefore, in the mixing section, a mixed liquid (ink) having an accurate density can be quickly formed, and printing can be performed with an accurate print density, and the printing speed can be increased.

Further, in the on-demand type ink jet printer according to the present invention, the transparent solvent as the first liquid is pressurized in the pressure transmission chamber, and the mixing section provided near the discharge port of the pressure transmission chamber includes: An on-demand type ink jet printer having a head unit for intermittently discharging the transparent solvent and an ink which is a second liquid separately supplied, wherein the control unit controls an applied electric field. The first and second electro-osmotic portions of the first and second two-layer porous membranes, which allow ink to pass through in a direction corresponding to the direction, are alternately sandwiched between first to third three mesh electrodes. 3) controlling the pulse applying means so that a driving voltage pulse of a predetermined polarity is applied between one of the electrodes between the third mesh electrode and the second mesh electrode to make the electroosmotic portion in a transmission state; In addition, the first and third menus Respectively between the shoe electrode and said second mesh electrode by controlling the pulse applying means so that the driving voltage pulse of the same polarity is applied to the dynamic stationary state the electroosmotic unit.

As a result, an electric field having a polarity opposite to the direction in which the ink permeates is formed between one of the electrodes, and the braking force acts to prevent wasteful ink flow. be able to. Therefore, a mixed solution having an accurate concentration can be quickly formed in the mixing section. Further, the response speed of the electroosmosis phenomenon can be increased, and the ink can be accurately quantified and supplied to the mixing section. Therefore, in the mixing section,
It is possible to quickly form a mixture (ink) with the correct density, and print with the correct print density.
This can contribute to a higher printing speed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a head portion of an on-demand type ink jet printer according to a first embodiment of the present invention provided with an electroosmotic membrane device according to the first embodiment of the present invention.

FIG. 2 is a cross-sectional view of an ink quantification unit which is the electroosmotic membrane device according to the first embodiment.

FIG. 3 is an overall block diagram of an on-demand type ink jet printer according to the first embodiment.

FIG. 4 is a time chart for explaining the operation of the ink quantification unit.

FIG. 5 is a block diagram of another control system for controlling the ink quantification unit.

FIG. 6 is a time chart for explaining the operation of the ink quantification unit by the other control system.

FIG. 7 is a perspective view of a main part of the on-demand type ink jet printer according to the first embodiment when the head section is a single orifice.

FIG. 8 is a perspective view of a main part of the on-demand type ink jet printer according to the first embodiment when the head section is a multi-orifice.

FIG. 9 is a cross-sectional view of an ink quantification unit, which is an electro-osmotic membrane device according to a second embodiment of the present invention, provided in an on-demand type ink jet printer device according to a second embodiment of the present invention. .

FIG. 10 is a time chart for explaining the operation of an ink quantification unit of the on-demand type ink jet printer of the second embodiment.

FIG. 11 is a cross-sectional view of the ink quantification unit of the on-demand type ink jet printer according to the second embodiment, illustrating the ink dynamic quiescent state of the ink quantification unit.

FIG. 12 is a cross-sectional view of the ink quantification unit for explaining the transmission state of the ink quantification unit of the on-demand type inkjet printer device according to the second embodiment.

FIG. 13 is a sectional view of a head portion of the conventional on-demand type ink jet printer.

FIG. 14 is a time chart for explaining a control operation of a head unit of the conventional on-demand type ink jet printer.

FIG. 15 is a block diagram of a control system for controlling a head unit of the conventional on-demand type ink jet printer.

[Explanation of symbols]

 1... Head section 2... Ink quantification section 3... Pressure transmission chamber 4. ... Electrostrictive vibrator 5 ... Mixing section 6 ... Orifice 7 ... Ink solution supply path 8 ... ·········· Orifice plate 10 ···································································································· 1 ... mesh electrode 13 ... electroosmotic part 14 ... 1st ink chamber 15 ... 2nd ink chamber 16 ... ... First ink supply path 17 Second ink supply path 18 Input terminal 26 Memory 27 ............. Correction circuit 28・ ・ ・ ・ ・ ・ ・ ・ ・ Driver 29 ・ ・ ・ ・ ・ ・ ・ ・ ・ Control system 30 ・ ・ ・ ・ ・ ・ ・ ・ ・ Control circuit 31 ・ ・ ・ ・ ・ ・ ・ ・ ・ First pulse generation circuit 32 second pulse generation circuit 33 PZT drive waveform generation circuit 34 to 36 amplifier 41, 51 Recording paper 42, 53, 73 Small roller 43 Belt 44, 52, 72 Drum 45, 55 Moving shaft 60 ... Multi-orifice head 80... Head part 81... First mesh electrode 82. ... Third mesh electrode 84... Electroosmosis membrane part 85... First ink chamber 86. ... Second ink chamber 87... First ink supply path 88... Second ink supply path 89, 90. ... Input terminal 91... First porous film 92... Second porous film

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B41J 2/205 B01J 4/04

Claims (5)

(57) [Claims] 1. A first and a second two-layered porous membrane that allows a liquid to permeate in a direction corresponding to the direction of an applied electric field are alternately sandwiched between first to third three mesh electrodes. An electroosmosis section, pulse applying means for applying a drive voltage pulse between the first and third mesh electrodes and the second mesh electrode, respectively, and the first and third mesh electrodes and the Controlling the pulse applying means so that a driving voltage pulse of a predetermined polarity is applied between one electrode between the two mesh electrodes to bring the electroosmotic portion into a transmissive state; Control means for controlling the pulse applying means so that a driving voltage pulse of the same polarity is applied between the mesh electrode and the second mesh electrode to bring the electroosmotic part into a dynamic stationary state. Characteristic electroosmosis membrane device. 2. The control device according to claim 1, wherein the direction of the electric field between the first and third mesh electrodes and the second mesh electrode is:
By controlling the pulse applying means so that a driving voltage pulse in the direction of the second mesh electrode is respectively applied between the electrodes, the electroosmotic unit is brought into the dynamic stationary state. The electroosmotic membrane device according to claim 1, wherein 3. The first liquid is pressurized in a pressure transmission chamber, and the first liquid is mixed in a mixing section provided near a discharge port of the pressure transmission chamber.
An on-demand type ink jet printer device having a head unit for intermittently discharging a mixture of a liquid and a second liquid separately supplied, the liquid being supplied in a direction corresponding to the direction of an applied electric field. An electroosmotic portion having a porous membrane to be permeated interposed between first and second mesh electrodes; a pulse applying means for applying a drive voltage pulse between the mesh electrodes of the electroosmotic portion; a mesh electrode of the electroosmotic portion While controlling the pulse applying means so that a drive voltage pulse of a predetermined polarity is applied in between, and after applying the drive voltage pulse of the predetermined polarity, the drive voltage pulse of the opposite polarity to the drive voltage pulse of the predetermined polarity is applied. Control means for controlling the pulse applying means so that a driving voltage pulse is applied between the mesh electrodes for a predetermined time. The other apparatus. 4. The first liquid is pressurized in a pressure transmission chamber, and the first liquid is mixed in a mixing section provided near a discharge port of the pressure transmission chamber.
An on-demand type ink jet printer device having a head section for intermittently discharging a mixture of a liquid and a second liquid supplied separately, wherein the liquid is supplied in a direction corresponding to the direction of an applied electric field. An electroosmotic section in which first and second two-layered porous membranes to be permeated are alternately sandwiched between first to third three mesh electrodes, the first and third mesh electrodes and the second Pulse applying means for applying a driving voltage pulse to each of the mesh electrodes, and a driving voltage pulse having a predetermined polarity between one of the first, third, and second mesh electrodes. The electroosmotic portion is made to be in a transmitting state by controlling the pulse applying means so that a driving voltage pulse of the same polarity is respectively applied between the first and third mesh electrodes and the second mesh electrode. Is applied as above By controlling the pulse applying means on-demand type ink jet printer apparatus characterized by a control means to dynamically stationary state the electroosmotic unit. 5. The on-demand type ink jet printer device according to claim 3, wherein the first liquid is a transparent solvent, and the second liquid is an ink.