JP3116661B2 - Ink jet 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 ink jet apparatus.

[0002]

2. Description of the Related Art Conventionally, a drop-on-demand type ink jet printer head using piezoelectric ceramics has been proposed as a printer head. This is because, by changing the volume of the ink liquid chamber by deformation of the piezoelectric ceramics, the ink in the ink liquid chamber is ejected as droplets from the nozzle when the volume decreases, and when the volume increases, the ink enters the ink liquid chamber from the other ink introduction path. Ink is introduced. A large number of such ink liquid chambers are arranged close to each other, and ink droplets are ejected from a nozzle at a desired position in accordance with desired print data. An image is formed.

[0003] For example, Japanese Patent Application Laid-Open Nos. 63-27051 and 63-252 disclose such an ink ejecting apparatus.
750 and JP-A-2-150355. FIG. 29, FIG. 30, FIG. 31, FIG.
2 and 33 are schematic diagrams of the conventional examples. Hereinafter, the configuration of the conventional example will be specifically described with reference to FIG. 29 showing a cross-sectional view of the ink ejecting apparatus. The piezoelectric ceramic plate 1 having the plurality of grooves 15 and the side walls 11 separating the grooves 15 and having been subjected to polarization processing in the direction of arrow 4 and the cover plate 2 made of a ceramic material or a resin material are bonded by epoxy bonding. The groove 15 becomes a plurality of ink liquid chambers 12 that are spaced apart from each other in the lateral direction by being joined by the joining layer 3 made of an agent or the like. The ink liquid chamber 12 has an elongated shape with a rectangular cross section, and the side wall 11 extends over the entire length of the ink liquid chamber 12. Metal electrodes 13 for applying a driving electric field are formed on both surfaces from the upper portion of the side wall 11 near the adhesive layer 3 to the center of the side wall 11. All the ink liquid chambers 12 are filled with ink.

Next, FIG. 3 is a sectional view of an ink ejecting apparatus.
With reference to 0, the operation of the conventional example will be described. In the ink ejecting apparatus, for example, when the ink liquid chamber 12b is selected according to desired print data, a positive driving voltage is rapidly applied to the metal electrodes 13e and 13f, and the metal electrodes 13d and 13g are applied.
Is grounded. As a result, a driving electric field in the direction of arrow 14b acts on the side wall 11b, and a driving electric field in the direction of arrow 14c acts on the side wall 11c. At this time, since the driving electric field directions 14b and 14c are orthogonal to the polarization direction 4, the side walls 11b
And 11c are rapidly deformed toward the inside of the ink liquid chamber 12b due to the piezoelectric thickness-shear effect. Due to this deformation, the volume of the ink liquid chamber 12b decreases, the ink pressure in the ink liquid chamber 12b rapidly increases, a pressure wave is generated, and the ink droplets from the nozzle 32 (FIG. 31) communicating with the ink liquid chamber 12b. Is injected. When the application of the driving voltage is gradually stopped, the side walls 11b and 11c are moved to the positions before deformation (FIG. 29).
(See FIG. 31), the ink pressure in the ink liquid chamber 12b gradually decreases, and ink is supplied from the ink supply port 21 (FIG. 31) into the ink liquid chamber 12b through the manifold 22 (FIG. 31).

In this ink ejecting apparatus, ink droplets cannot be ejected from two nozzles communicating with two adjacent ink liquid chambers at the same time. Therefore, for example, the ink communicating with odd-numbered ink liquid chambers 12a and 12c from the left end. Nozzle 3
After the ink droplets are ejected from the second ink droplets, the ink droplets are ejected from the nozzles 32 communicating with the even-numbered ink liquid chambers 12b and 12d, and then the ink droplets are ejected again from the odd-numbered ink chambers. The chamber 12 and the nozzles 32 are divided into a plurality of groups to eject ink droplets.

However, the above operation is only a basic operation of the conventional example, and when embodied as a product, a driving voltage is first applied in a direction of increasing the volume, and the driving voltage is first applied to the ink liquid chamber 12b. After the ink is supplied, the above operation may be performed.

Next, FIG. 3 shows a perspective view of the ink ejecting apparatus.
1, the configuration and manufacturing method of the conventional example will be described. The parallel grooves 1 forming the ink liquid chambers 12 having the above-mentioned shape are formed on the piezoelectric ceramic plate 1 that has been subjected to the polarization treatment by grinding using a thin disk-shaped diamond blade or the like.
5 are produced. The groove 15 is for the piezoelectric ceramic plate 1
Are parallel in the same depth over almost the entire area, but gradually become shallower as approaching the end face 17, and become shallow and parallel shallow grooves 18 near the end face 17. The metal electrodes 13 are formed on the inner surfaces of the groove 15 and the shallow groove 18 by sputtering or the like. The metal electrode 13 is formed only on the upper half of the side surface on the inner surface of the groove 15, while the metal electrode 13 is formed on the entire side surface and bottom surface of the shallow groove 18. Further, an ink inlet 21 and a manifold 22 are formed on the cover plate 2 made of a ceramic material or a resin material by grinding or cutting.

Next, the grooves 1 of the piezoelectric ceramic plate 1
The surface on the processing side 5 and the surface on the processing side of the manifold 22 of the cover plate 2 are adhered by an epoxy-based adhesive or the like such that the respective grooves 15 form the ink liquid chamber 12 having the above-described shape. Next, a nozzle plate 31 provided with nozzles 32 at positions corresponding to the positions of the respective ink liquid chambers 12 is bonded to the end surfaces 16 of the piezoelectric ceramic plate 1 and the cover plate 2. Groove 1 of piezoelectric ceramic plate 1
5 On the surface opposite to the processing side, a substrate 41 provided with a conductive layer pattern 42 at a position corresponding to the position of each ink liquid chamber 12 is adhered by an epoxy adhesive or the like. Then, the metal electrode 13 on the bottom surface of the shallow parallel groove 18 and the pattern 42 of the conductive layer are connected by a conductive wire 43 by well-known wire bonding.

Next, the configuration of a conventional control unit will be described with reference to FIG. 32 showing a block diagram of the control unit. The conductive layer patterns 42 provided on the substrate 41 are individually connected to the LSI chip 51, and the clock line 52, the data line 53, the voltage line 54, and the ground line 55 are also connected to the LSI chip 51.
It is connected to a chip 51. The LSI chip 51 determines from the data appearing on the data line 53 which nozzle 32 should eject the ink droplet based on the continuous clock pulse supplied from the clock line 52, The voltage V of the voltage line 54 is applied to the conductive layer pattern 42 that is electrically connected to the metal electrode 13 in the chamber 12. Further, a voltage 0 of the ground line 55 is applied to the conductive layer pattern 42 that is electrically connected to the metal electrode 13 other than the ink liquid chamber 12.

Next, the configuration and operation of the conventional example will be described with reference to FIG. 33 showing a perspective view of a printer. The ink ejection device 61 and the nozzle plate 31 have the configuration and operation described with reference to FIGS. 29, 30, and 31. The ink ejection device 61 is fixed on a carriage 62, and an ink supply tube 63 connected to an ink tank (not shown) communicates with the ink supply port 21 (FIG. 31).
1 (FIG. 32) is built in the carriage 62, and the flexible cable 64 is connected to the clock line 52 shown in FIG.
Data line 53, voltage line 54 and earth line 5
5 is supported. The carriage 62 reciprocates along the slider 66 in the direction of the arrow 65 over the entire width of the recording paper 71, and the ink ejecting device 61 moves the nozzle against the recording paper 71 held by the platen roller 72 while the carriage 62 is moving. Nozzle 32 provided on plate 31
Ink droplets are ejected from FIG. 31 to adhere the ink droplets on the recording paper 71.

The recording paper 71 is stationary when the ink ejecting device 61 ejects ink droplets, but each time the carriage 62 reciprocates, it is moved in the direction of arrow 75 by the paper feed rollers 73 and 74. It is transferred by a fixed amount. Thus, the ink ejecting apparatus 61 can form desired characters and images on the entire surface of the recording paper 71.

[0012]

However, the above-mentioned conventional Japanese Patent Application Laid-Open Nos. 63-247051, 63-252750 and 2-150355.
In the ink jetting device 61 described in Japanese Patent Application Laid-Open No. H11-207, when ink is jetted from a certain ink liquid chamber 12b, a pressure wave is generated in the adjacent ink liquid chambers 12a and 12c. Even if ink is ejected from the chambers 12a and 12c, the volume of ejected ink droplets differs or the ink droplets are not ejected, resulting in poor print quality. The period of the pressure oscillation varies depending on the nozzle reflection coefficient, but is from 3 L / a to 6 L / a.
It is about. L / a is the time required for the pressure wave in the ink liquid chamber 12 to propagate one way in the longitudinal direction of the ink liquid chamber 12 (from the manifold 22 to the nozzle plate 31 or vice versa). It is determined by the length L of the chamber 12 and the sound speed a in the ink. For example, if the length L of the ink liquid chamber 12 is 4 mm, L / a is 6 μsec, and if the length L is 15 mm, L / a is 25 μsec.

Therefore, in order to eject ink droplets from the ink liquid chambers 12 and the nozzles 32 divided into a plurality of groups, the ink liquid chambers 12 and the nozzles 32 of a certain group are ejected.
Only after the pressure oscillation in the ink liquid chambers 12 of the adjacent group stops after the ink droplets are jetted from the ink droplets, the ink droplets can be jetted from the ink liquid chambers 12 and the nozzles 32 of the adjacent group. Did not. Therefore, the conventional ink ejecting apparatus 61 has a problem that the frequency of ejecting ink droplets is low and the printing speed is slow.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide an ink ejecting apparatus having a high printing speed.

[0015]

In order to achieve the above object, according to the first aspect of the present invention, a pressure separating a plurality of ink liquid chambers is provided.
Two ink liquid chambers which are adjacent to each other
When one of the ink chambers is enlarged, the other ink chamber is
A partition deforms to contract, a supply source for supplying ink to the ink chamber, because the deformation of the partition wall to the partition wall
Control means for applying a voltage of
Marking of voltage on the partition walls on both sides of the ink liquid chamber to be tried
In addition, the partition walls are moved from the neutral position to the ink liquid respectively.
The ink liquid is deformed inward without deforming to the outside of the chamber.
When the volume of the chamber is contracted, ink is not ejected.
Both partition walls change from the neutral position to the outside of the ink chamber.
And then expand the volume of the ink liquid chamber.
When the volume of the ink liquid chamber shrinks due to inward deformation
Ejecting ink, an ink jet apparatus, wherein, when ejecting the ink from both the first ink chamber and a second ink chambers adjacent to each other physician, the first ink
The partition on both sides of the liquid chamber is moved from the neutral position to the first ink liquid chamber.
To expand the volume of the first ink liquid chamber,
After supplying ink to the first ink liquid chamber, the two partition walls are
Deflected from the neutral position to the inside of the first ink liquid chamber and
At the same time as reducing the volume of one ink chamber, the second ink
A gap on the side of the liquid chamber facing the partition between the first ink liquid chamber.
The wall is deformed to the outside of the second ink liquid chamber so that the second ink liquid
Supplying ink to the second ink liquid chamber by expanding the volume of the chamber
Then, the partition walls are moved from the neutral position to the second ink.
Deforms to the inside of the liquid chamber to shrink the volume of the second ink liquid chamber
That way, and applying a voltage to said partition wall.

[0016] According to claim 2, in the configuration of claim 1, wherein, prior Symbol control means, only the ratio L / a of the speed of sound a in a length L and the ink in the ink chamber, the ink chamber It is characterized in that a voltage is applied in a direction of expanding the volume and in a direction of contracting the volume.

[0017]

In the ink ejecting apparatus according to the present invention having the above-described structure, the control means ejects ink from both the first ink liquid chamber and the second ink liquid chamber adjacent to each other among the plurality of ink liquid chambers. The ink chambers on both sides of the first ink chamber.
The wall is deformed from the neutral position to the outside of the first ink liquid chamber to
Enlarge the volume of the first ink liquid chamber, and
After the supply of ink, the partition walls are moved to the neutral position and the first
To the inside of the ink chamber to accommodate the volume of the first ink chamber.
Shrink and eject ink. Shrink the volume of the first ink chamber
At the same time as the second ink liquid chamber and the first ink liquid chamber
The partition opposite to the partition between the outside of the second ink liquid chamber
To increase the volume of the second ink liquid chamber,
Supply ink to the ink liquid chamber, then place both partition walls in neutral position
To the inside of the second ink liquid chamber, and
The volume of the liquid chamber is contracted to eject ink .

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings. The same members as those in the related art are denoted by the same reference numerals, and description thereof will be omitted.

FIGS. 1, 3, 5, 7, 9, 11, and 13 showing sectional views of the ink ejecting apparatus, and FIG. 2 showing a drive voltage waveform of the electrode 13 in the ink liquid chamber 12. The configuration and operation of the first embodiment of the present invention will be described with reference to FIG. 4, FIG. 6, FIG. 8, FIG. 10, FIG.

F indicates when ink droplets are ejected from the nozzles 32 of a certain ink liquid chamber 12, and N indicates when ink droplets are not ejected. The ink liquid chambers 12a, 12b, 12c, and 12d (FIG. 3)
0), the nozzles 32a, 32b, 32c, and 3 (not shown).
2d, the ejection pattern of the ink droplets from the nozzles 32 is expressed by arranging F or N in this order.
For example, FNNF indicates that ink droplets are ejected from the nozzles 32a and 32d of the ink liquid chambers 12a and 12d, but not ejected from the nozzles 32b and 32c of the ink liquid chambers 12b and 12c. Here, the ink liquid chambers 12x and 12y serving as both ends of the ink liquid chamber 12 are provided as ink liquid chambers that do not eject ink, and only one wall is deformed.
The width of the voltage applied to deform the side wall 11 is L / a. In this embodiment, the length of the ink liquid chamber 12 is 4 mm, and L / a is 6 μsec.

The case where the injection pattern is FFFF will be described with reference to FIGS. FIG. 1 (a),
(B), (c), (d), and (e) respectively show the drive voltage waveforms (a), (b), (c), (d), and (d) of FIG.
The state of deformation of the side wall 11 at the timing shown in FIG. Then, the driving voltage waveform (a) in FIG.
The width of (b), (c), (d), and (e) is L / a.

In (a), the drive voltages of all the electrodes 13 are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), a negative drive voltage -V is applied to the electrode 13 formed in the ink liquid chamber 12a. Then
Since the direction of the electric field is opposite to that of the side walls 11b and 11c on both sides of the ink liquid chamber 12b of the conventional example described in FIG. 30, the side walls 11a and 11b on both sides of the ink liquid chamber 12a change from the neutral state (natural state) to the ink liquid state. It rapidly deforms in the outward direction of the chamber 12a. A state where the volume of the ink liquid chamber 12a is expanded from a natural state due to this deformation (hereinafter, referred to as an expanded state).
The ink pressure in the ink liquid chamber 12a rapidly decreases, and the ink supply tube 6
3 (FIG. 33), ink is supplied into the ink liquid chamber 12a through the ink supply port 21 (FIG. 31), and the manifold 22 (FIG. 31). At this time, the negative drive voltage -V is also applied to the electrode 13 formed in the ink liquid chamber 12c,
Similarly, the volume of the ink liquid chamber 12c is increased, and ink is supplied.

Due to the expansion of the volumes of the ink liquid chambers 12a and 12c, the ink liquid chamber 12b between the ink liquid chamber 12a and the ink liquid chamber 12c is moved from the neutral state of the side walls 11b and 11c on both sides to the inside of the ink liquid chamber 12b. The ink liquid chamber 12b is rapidly deformed in the direction, and the volume of the ink liquid chamber 12b is contracted (hereinafter, referred to as contracted state), and the ink pressure increases. However, the pressure generated in the ink liquid chamber 12b is only about half of the pressure generated when the ink liquid chamber 12 is expanded from the expanded state to the contracted state beyond the natural state, and communicates with the ink liquid chamber 12b. No ink droplets are ejected from the nozzles 32.

In (c), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chambers 12a, 12c and 12y, and the side walls 11a, 11b and 11c on both sides of the ink liquid chambers 12a and 12c. , 11d rapidly deform inward from the outwardly deformed state through the neutral state. Therefore, the volumes of the ink liquid chambers 12a and 12c change from the expanded state to the contracted state through the natural state, the ink pressure in the ink liquid chambers 12a and 12c rapidly increases, and the nozzles 32a and 3
An ink droplet is ejected from 2c. At this time, the ink liquid chambers 12b and 12d are in an expanded state, the ink pressure in the ink liquid chambers 12b and 12d is rapidly reduced, and an ink supply tube (not shown) is connected to an ink supply tube (not shown).
3), ink supply port 21 (FIG. 31), manifold 22
The ink is supplied into the ink liquid chambers 12b and 12d through (FIG. 31).

Next, in (d), the ink liquid chambers 12b and 1b
The positive drive voltage V is applied only to the electrode 13 formed inside 2d.
Is applied, the side walls 11 of the ink liquid chambers 12b and 12d are deformed, the ink liquid chambers 12b and 12d are changed from the expanded state to the contracted state through the natural state, and the ink droplets are ejected from the nozzles 32.

In (e), the drive voltage of all the electrodes 13 is 0
And all the ink liquid chambers 12 are in the natural state, and the ejection pattern FFFF ink ejection ends.

Incidentally, the electrode 13 of the ink liquid chamber 12 is used.
The control of the voltage to the LSI is performed by an LSI chip (not shown) as in the conventional case.

Next, when the injection pattern is FFFN,
This will be described with reference to FIGS.

In (a), the drive voltages of all the electrodes 13 are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), a negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chambers 12a and 12c, and the ink liquid chambers 12a and 12c are expanded in volume to supply ink. You.

In (c), a positive drive voltage V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a and 12c, and the ink liquid chambers 12a and 12c change from the expanded state to the contracted state through the natural state. And the nozzles 32a and 32c
Ejects ink droplets. At this time, the ink liquid chamber 12
b is in an expanded state and ink is supplied.

In (d), a positive driving voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b contracts from the expanded state through a natural state, and the ink liquid chamber 12b enters the contracted state from the nozzle 32b. Droplets are ejected.

In (e), the drive voltage of all the electrodes 13 is 0
And all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FFFN is completed.

When the injection pattern is NFFF, the configuration and operation are the same.

Next, when the injection pattern is FFNF,
This will be described with reference to FIGS.

In (a), the drive voltages of all the electrodes 13 are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), a negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chambers 12a and 12d, and the ink liquid chambers 12a and 12d are in an expanded state and ink is supplied.

In (c), only the electrode 13 formed inside the ink liquid chambers 12b and 12x has a negative drive voltage -V, and only the electrode 13 formed inside the ink liquid chamber 12d has a positive drive voltage V. Is applied. Then, the ink liquid chambers 12a and 12d change from the expanded state to the contracted state through the natural state, and the ink droplets are ejected from the nozzles 32a and 32d, and the ink liquid chamber 12b is expanded and the ink is supplied.

In (d), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from b.

In (e), the drive voltage of all the electrodes 13 is 0
And all the ink liquid chambers 12 are in a natural state, and the ejection pattern FFNF ink ejection ends.

When the injection pattern is FNFF, the configuration and operation are the same.

Next, when the injection pattern is FFNN,
This will be described with reference to FIGS.

In (a), the drive voltages of all the electrodes 13 are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), the negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a is expanded to supply ink.

In (c), a negative drive voltage -V is applied only to the electrodes 13 formed inside the ink liquid chambers 12b and 12x, and the ink liquid chamber 12a changes from an expanded state to a contracted state, and the ink liquid 12 Droplets are ejected, and the ink liquid chamber 12b is expanded so that ink is supplied.

In (d), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from b.

In (e), the drive voltages of all the electrodes 13 are set to 0, all the ink liquid chambers 12 are in a natural state, and the ink ejection of the ejection pattern FFNN is completed.

The injection patterns are NNFF and NFFF
In this case, the configuration and operation are the same.

Next, when the injection pattern is FNFN,
This will be described with reference to FIGS. In (a), the drive voltages of all the electrodes are 0, and the ink liquid chamber 12 is in a natural state.

In (b), the negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a is in an expanded state and ink is supplied.

In (c), only the electrode 13 formed inside the ink liquid chamber 12c has a negative drive voltage -V,
The positive drive voltage V is applied only to the electrode 13 formed inside 2a.
Is applied. Then, the ink liquid chamber 12a is changed from the expanded state to the contracted state, and the ink droplets are ejected from the nozzle 32a, and the ink liquid chamber 12c is expanded and the ink is supplied.

In (d), the positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12c, and the ink liquid chamber 12c changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from c.

In (e), the drive voltage of all the electrodes 13 is 0
Then, all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FNFN is completed.

When the injection pattern is NFNF, the configuration and operation are the same.

Next, when the injection pattern is FNNF,
This will be described with reference to FIGS.

In (a), the drive voltages of all the electrodes are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), a negative drive voltage -V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a and 12d, and the ink liquid chambers 12a and 12d are in an expanded state and ink is supplied.

In (c), a positive drive voltage V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a and 12d, and the ink liquid chambers 12a and 12d are changed from the expanded state to the contracted state, and the nozzles 32a and 32d are turned. Ejects ink droplets.

In (d), the drive voltages of all the electrodes are set to 0, all the ink liquid chambers 12 are in a natural state, and the ink ejection of the ejection pattern FNNF is completed.

Next, the case where the injection pattern is FNNN is as follows:
This will be described with reference to FIGS.

In (a), the drive voltages of all the electrodes 13 are 0, and all the ink liquid chambers 12 are in a natural state.

In (b), a negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a is in an expanded state and ink is supplied.

In (c), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from a.

In (d), the drive voltage of all the electrodes 13 is 0
And all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FNNNN is completed.

The injection pattern is NFNN, NNNF,
The configuration and operation of the NNNF are the same as those described above.

When the ejection pattern is NNNN, the drive voltages of all the electrodes 13 are held at zero.

The voltage control for the electrodes 13 is performed by an LSI chip.

As described above, in the ink ejecting apparatus of the first embodiment, the ink droplets are ejected from, for example, both of the ink chambers 12a and 12b adjacent to each other among the plurality of ink chambers 12. The ink chamber 12
In the contracted state of the ink liquid chamber 12a for ejecting ink from a, the ink liquid chamber 12b is expanded to supply ink, and after the L / a (6 μsec in this embodiment), the ink liquid chamber 12b is contracted from the expanded state. Since the ink is ejected as the state, the ink droplet is ejected from the nozzle 32b after L / a ejected from the nozzle 32a. Accordingly, two ink liquid chambers 12 that are adjacent to each other communicate with each other.
The ink droplets can be ejected from the two nozzles 32a and 32b in a very short time (approximately simultaneously) of L / a (6 μsec in this embodiment).

After the ink droplets are ejected from a certain group of ink liquid chambers 12 and nozzles 32 in the conventional example, the vibration of the pressure in the adjacent group of ink liquid chambers 12 stops, and Comparing the ink ejecting apparatus 61 (FIG. 33) which ejects ink droplets from the ink liquid chamber 12 and the nozzle 32 with the ink ejecting apparatus of the first embodiment, the frequency of ejecting ink droplets is significantly higher. . For this reason, it is possible to provide an ink ejecting apparatus having a high printing speed.

Next, a plurality of ink droplets, which embody the present invention, are ejected from a certain ink liquid chamber, and these ink droplets are integrated during flight by the surface tension of the ink. A second embodiment for forming ink droplets will be described with reference to the drawings. The same members as those in the prior art and the first embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIGS. 15, 17, 19, which show sectional views of the ink ejecting apparatus.
21, 23, 25, 27, and ink liquid chamber 1
16, 18 and 2 showing the drive voltage of the electrode 13 in FIG.
The configuration and operation of the second embodiment of the present invention will be described with reference to FIGS. 0, 22, 24, 26, and 28.

First, when the injection pattern is FFFF,
This will be described with reference to FIGS. (A) of FIG.
(B), (c), (d), (e), (f), (g)
The drive voltage waveforms (a), (b), and (b) of FIG.
The deformation state of the side wall 11 at the timings described in (c), (d), (e), (f), and (g) is shown. 1A to 1C and FIGS. 15A to 15C described in the first embodiment.
Since (c) is the same operation, its description is omitted.

In (d), the negative drive voltage −V is applied to the electrodes 13 formed inside the ink liquid chambers 12a, 12c and 12y.
Is applied. Then, the ink liquid chambers 12a and 12c are changed from the contracted state to the expanded state, and the ink is supplied. The ink liquid chambers 12b and 12d are changed from the expanded state to the contracted state, and the ink droplets are ejected from the nozzles 32b and 32d. In (e), a positive drive voltage V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a, 12c and 12y. Then, the ink liquid chambers 12a and 12c are changed from the expanded state to the contracted state, and the ink droplets are ejected from the nozzles 32a and 32c, and the ink liquid chambers 12b and 12d are changed from the contracted state to the expanded state and the ink is supplied. At this time, the respective ink droplets ejected from the nozzles 32a and 32c are caused by the nozzle 3 in FIG.
Each of the ink droplets ejected from the nozzles 2a and 32c is integrated with the ink droplets during flight to form respective integrated ink droplets. Next, in (f), a positive drive voltage V is applied only to the electrodes 13 formed inside the ink liquid chambers 12b and 12d, and the side walls 11 of the ink liquid chambers 12b and 12d are deformed, so that the ink liquid chambers 12b and 12d are deformed. The nozzles 32b and 32d eject ink droplets from the nozzles 32b and 32d from the expanded state to the contracted state through the natural state. Each of the ink droplets ejected at this time is caused by (d) due to the surface tension of the ink.
The ink droplets are integrated with the respective ink droplets ejected from the nozzles 32b and 32d during flight to form respective integrated ink droplets.

In (g), the drive voltages of all the electrodes 13 are 0
And all the ink liquid chambers 12 are in the natural state, and the ejection pattern FFFF ink ejection ends.

Incidentally, the electrode 13 of the ink liquid chamber 12 is used.
The control of the voltage to the LSI chip is performed by the LSI chip.

Next, when the injection pattern is FFFN,
This will be described with reference to FIGS. 3 (a) to 3 (c) and FIGS. 17 (a) to 17 (c) described in the first embodiment are the same operations, and a description thereof will be omitted.

In (d), a negative drive voltage -V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a and 12c. Then, the ink liquid chamber 12b changes from the expanded state to the contracted state, and ink droplets are ejected from the nozzle 32b.
The ink liquid chambers 12a and 12c change from the contracted state to the expanded state, and the ink is supplied.

In (e), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chambers 12a and 12c. Then, the ink liquid chambers 12a and 12c are changed from the expanded state to the contracted state, and the ink droplets are ejected from the nozzles 32a and 32c, and the ink liquid chamber 12b is changed from the contracted state to the expanded state and the ink is supplied. These ejected ink droplets are combined with the respective ink droplets ejected from the nozzles 32a and 32c in (c) during flight to become respective integrated ink droplets.

In (f), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b contracts from the expanded state through a natural state, and the ink liquid chamber 12b enters the contracted state from the nozzle 32b. Droplets are ejected. The ejected ink droplet is integrated with the ink droplet ejected from the nozzle 32b in (d) during flight to become an integrated ink droplet.

In (g), the drive voltages of all the electrodes 13 are 0
And all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FFFN is completed.

When the injection pattern is NFFF, the configuration and operation are the same.

Next, when the injection pattern is FFNF,
This will be described with reference to FIGS. 5 (a) to 5 (c) and FIGS. 19 (a) to 19 (c) described in the first embodiment are the same operations, and a description thereof will be omitted.

In (d), only the electrode 13 formed inside the ink liquid chamber 12d has the negative drive voltage −V and the ink liquid chamber 1
A positive drive voltage V is applied only to the electrodes 13 formed inside 2b and 12x. Then, the ink liquid chamber 12b is changed from the expanded state to the contracted state, and the ink droplets are ejected from the nozzle 32b, and the ink liquid chambers 12a and 12d are changed from the contracted state to the expanded state, and the ink is supplied.

In (e), only the electrode 13 formed inside the ink liquid chambers 12b and 12x has a negative driving voltage -V, and only the electrode 13 formed inside the ink liquid chamber 12d has a positive driving voltage V. Is applied. Then, the ink liquid chambers 12a and 12d change from the expanded state to the contracted state, and the ink droplets are ejected from the nozzles 32a and 32d, and the ink liquid chambers 12b
Changes from the contracted state to the expanded state, and ink is supplied. At this time, the respective ink droplets ejected from the nozzles 32a and 32d are integrated with the respective ink droplets ejected from the nozzles 32a and 32d during the flight in FIG. Become.

In (f), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b is in a contracted state, and ink droplets are ejected from the nozzle 32b. This ejected ink droplet is
In (d), the ink droplet ejected from the nozzle 32b is integrated with the ink droplet during flight to become an integrated ink droplet.

In (g), the drive voltages of all the electrodes 13 are 0
And all the ink liquid chambers 12 are in a natural state, and the ejection pattern FFNF ink ejection ends.

When the injection pattern is FNFF, the configuration and operation are the same.

Next, when the injection pattern is FFNN,
This will be described with reference to FIGS. 7 (a) to 7 (c) and FIGS. 21 (a) to 21 (c) described in the first embodiment are the same operations, and a description thereof will be omitted.

In (d), a positive drive voltage V is applied only to the electrodes 13 formed inside the ink liquid chambers 12b and 12x. Then, the ink liquid chamber 12b is changed from the expanded state to the contracted state, and the ink droplet is ejected from the nozzle 32b, and the ink liquid chamber 12a is changed from the contracted state to the expanded state, and the ink is supplied.

In (e), a negative drive voltage -V is applied only to the electrodes 13 formed inside the ink liquid chambers 12b and 12x. Then, the ink liquid chamber 12a changes from the expanded state to the contracted state, and ink droplets are ejected from the nozzle 32a.
The ink liquid chamber 12b changes from the contracted state to the expanded state, and the ink is supplied. The ink droplet ejected at this time is
The ink droplet ejected in (c) is integrated during flight into an integrated ink droplet.

(F), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12b, and the ink liquid chamber 12b changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from b. The ejected ink droplet is integrated with the ink droplet ejected in (d) during flight to become an integrated ink droplet.

In (g), the drive voltages of all the electrodes 13 are set to 0, all the ink liquid chambers 12 are in a natural state, and the ink ejection of the ejection pattern FFNN is completed.

The injection patterns are NNFF and NFFF
In this case, the configuration and operation are the same.

Next, when the injection pattern is FNFN,
This will be described with reference to FIGS. 9 (a) to 9 (c) and FIGS. 23 (a) to 23 (c) described in the first embodiment are the same operations, and therefore description thereof will be omitted.

In (d), only the electrode 13 formed inside the ink liquid chamber 12a has a negative drive voltage −V,
The positive drive voltage V is applied only to the electrode 13 formed inside 2c.
Is applied. Then, the ink liquid chamber 12c changes from the expanded state to the contracted state, and the ink droplets are ejected from the nozzle 32c, and the ink liquid chamber 12a changes from the contracted state to the expanded state, and ink is supplied.

In (e), only the electrode 13 formed inside the ink chamber 12c has a negative drive voltage -V,
The positive drive voltage V is applied only to the electrode 13 formed inside 2a.
Is applied. Then, the ink liquid chamber 12a changes from the expanded state to the contracted state, and the ink droplets are ejected from the nozzle 32a, and the ink liquid chamber 12c changes from the contracted state to the expanded state, and ink is supplied. The ink droplet ejected at this time is
The ink droplet ejected in (c) is integrated during flight into an integrated ink droplet.

(F), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12c, and the ink liquid chamber 12c changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from c. The ejected ink droplet is integrated with the ink droplet ejected in (d) during flight to become an integrated ink droplet.

In (g), the drive voltages of all the electrodes 13 are 0
Then, all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FNFN is completed.

When the injection pattern is NFNF, the configuration and operation are the same.

Next, when the injection pattern is FNNF,
This will be described with reference to FIGS. FIGS. 11 (a) to (c) and FIGS. 25 (a) to (c) described in the first embodiment are the same operations, and therefore description thereof is omitted.

In (d), the negative drive voltage -V is applied only to the electrodes 13 formed inside the ink liquid chambers 12a and 12d, and the ink liquid chambers 12a and 12d are changed from the contracted state to the expanded state, and the ink is supplied. Is done.

In (e), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chambers 12a and 12d, and the ink liquid chambers 12a and 12d are changed from the expanded state to the contracted state, and the nozzles 32a and 32d Ejects ink droplets. Each of the ink droplets ejected at this time is integrated with each of the ink droplets ejected in (c) during flight to become respective integrated ink droplets.

In (f), the drive voltages of all the electrodes 13 are set to 0, all the ink liquid chambers 12 are in a natural state, and the ink ejection of the ejection pattern FNNF is completed.

Next, the case where the injection pattern is FNNN is as follows.
This will be described with reference to FIGS. 27 and 28. FIGS. 11 (a) to (c) and FIGS. 25 (a) to (c) described in the first embodiment are the same operations, and therefore description thereof is omitted.

In (d), the negative drive voltage -V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a is changed from the contracted state to the expanded state, and the ink is supplied.

In (e), a positive drive voltage V is applied only to the electrode 13 formed inside the ink liquid chamber 12a, and the ink liquid chamber 12a changes from the expanded state to the contracted state, and the nozzle 32
An ink droplet is ejected from a. The ejected ink droplets are integrated with the ink droplet ejected in (c) during flight to become an integrated ink droplet.

In (f), the drive voltages of all the electrodes 13 are 0
And all the ink liquid chambers 12 are in the natural state, and the ink ejection of the ejection pattern FNNNN is completed.

The injection pattern is NFNN, NNFN,
The configuration and operation of the NNNF are the same as those described above.

When the ejection pattern is NNNN, the drive voltages of all the electrodes 13 are kept at 0.

The voltage control for the electrodes 13 is performed by the LSI chip.

As described above, in the ink jetting device of the second embodiment, integrated ink droplets are formed from the plurality of ink liquid chambers 12, for example, both of the adjacent ink liquid chambers 12a and 12b. At the time, when the ink liquid chamber 12a for ejecting ink droplets from the ink liquid chamber 12a is in a contracted state, the ink liquid chamber 12b is expanded to supply ink, and after the L / a (6 μsec in this embodiment), the ink In a contracted state in which the liquid chamber 12b is contracted to eject ink droplets, the ink liquid chamber 12a is expanded to supply ink, and after L / a, the ink liquid chamber 12b is changed from the expanded state to a contracted state. Then, this operation is repeated, and two ink droplets are ejected from the ink liquid chambers 12a and 12b, respectively. It is obtained by integrating the ink droplets forming the respective (two) integrated ink droplets. L / L in which an integrated ink droplet is formed by the ink liquid chamber 12a
a, an integrated ink droplet is formed by the ink liquid chamber 12b, so that two ink liquid chambers 12 adjacent to each other are formed.
L / a from two nozzles 32a and 32b communicating with
The integrated ink droplets can be ejected in a very short time (approximately simultaneously), which is 6 μsec in this embodiment.

The frequency of the ejection of the ink droplets is remarkably increased as compared with the case where the conventional ink ejection device forms integrated ink droplets. For this reason, it is possible to provide an ink ejecting apparatus having a high printing speed.

In the first embodiment and the second embodiment, the number of the ink liquid chambers 12 and the number of the nozzles 32 communicating with the ink liquid chambers are four, but the voltage applied to each ink liquid chamber 12 is taken into consideration. In this case, the number is not limited to four and may be any number.

In the first embodiment and the second embodiment, the polarization direction of the piezoelectric ceramic plate 1 is the direction of the arrow 4, but the polarization direction may be the opposite direction of the arrow 4. In this case, by reversing the positive and negative of the above-mentioned drive voltage,
The same operation as described above is performed.

Further, in the second embodiment, two ejected ink droplets are integrated during flight to form an integrated ink droplet, but three or more ink droplets are integrated to form an integrated ink droplet. The ink droplets may be used.

In the first and second embodiments, the ink is ejected by deforming the partition walls 11 on both sides of the ink liquid chamber 12. However, the deformation of one partition wall by changing the voltage value or the like. In this case, the present invention can be used even if the ink is ejected by ink jetting. In this case, there is no need to provide an ink liquid chamber that does not eject ink, such as the ink liquid chambers 12x and 12y of the present embodiment.

[0117]

As apparent from the above description, in the ink jetting apparatus of the present invention, ink is jetted from both the first ink liquid chamber and the second ink liquid chamber which are adjacent to each other among the plurality of ink liquid chambers. The ink chambers on both sides of the first ink chamber.
The wall is deformed from the neutral position to the outside of the first ink liquid chamber to
Enlarge the volume of the first ink liquid chamber, and
After the supply of ink, the partition walls are moved to the neutral position and the first
To the inside of the ink chamber to accommodate the volume of the first ink chamber.
Shrink and eject ink. Shrink the volume of the first ink chamber
At the same time as the second ink liquid chamber and the first ink liquid chamber
The partition opposite to the partition between the outside of the second ink liquid chamber
To expand the volume of the second ink liquid chamber,
Ink to the ink chamber, and then place both partitions in the neutral position.
To deform into the second ink liquid chamber,
The volume of the liquid chamber is contracted to eject ink. Therefore,
Replenish the ink liquid chamber to be ejected without fail.
And, of two mutually adjacent short period of time from the two nozzles communicating with the ink chamber Ki out to eject ink droplets (about the same time), the frequency of ejection of ink droplets becomes faster, the printing This has the effect of increasing the speed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating an operation of an ink ejecting apparatus according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 1 according to the first embodiment of the present invention.

FIG. 3 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 3 according to the first embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a drive voltage waveform of the operation of FIG. 5 according to the first embodiment of the present invention.

FIG. 7 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 8 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 8 according to the first embodiment of the present invention.

FIG. 9 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 10 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 9 according to the first embodiment of the present invention.

FIG. 11 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 12 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 11 according to the first embodiment of the present invention.

FIG. 13 is an explanatory diagram illustrating an operation of the ink ejection device according to the first embodiment of the present invention.

FIG. 14 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 13 according to the first embodiment of the present invention.

FIG. 15 is an explanatory diagram illustrating an operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 16 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 15 according to the second embodiment of the present invention.

FIG. 17 is an explanatory diagram showing the operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 18 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 17 according to the second embodiment of the present invention.

FIG. 19 is an explanatory diagram showing the operation of the ink jetting device according to the second embodiment of the present invention.

FIG. 20 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 19 according to the second embodiment of the present invention.

FIG. 21 is an explanatory diagram illustrating an operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 22 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 21 according to the second embodiment of the present invention.

FIG. 23 is an explanatory diagram showing the operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 24 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 23 according to the second embodiment of the present invention.

FIG. 25 is an explanatory diagram showing the operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 26 is an explanatory diagram showing drive voltage waveforms in the operation of FIG. 25 according to the second embodiment of the present invention.

FIG. 27 is an explanatory diagram showing the operation of the ink ejection device according to the second embodiment of the present invention.

FIG. 28 is an explanatory diagram showing a drive voltage waveform in the operation of FIG. 27 according to the second embodiment of the present invention.

FIG. 29 is a cross-sectional view of a conventional ink ejecting apparatus.

FIG. 30 is an explanatory view showing the operation of a conventional ink ejecting apparatus.

FIG. 31 is a perspective view of a conventional ink ejecting apparatus.

FIG. 32 is a block diagram of a control unit of a conventional example.

FIG. 33 is a perspective view of a conventional printer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Piezoelectric ceramic plate 2 Cover plate 11 Side wall 12 Ink liquid chamber 32 Injection nozzle

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B41J 2/045 B41J 2/055

Claims (2)

(57) [Claims] A piezoelectric element for separating the plurality of ink liquid chambers from each other;
One of the two ink liquid chambers adjacent to each other on the wall
When the ink chamber is expanded, the other ink chamber shrinks.
And a supply source for supplying ink to the ink liquid chamber, and a voltage for deforming the partition is applied to the partition.
Before the ink is to be ejected.
By applying a voltage to the partition walls on both sides of the ink liquid chamber,
The two partition walls are respectively moved from the neutral position to the outside of the ink liquid chamber.
Deforms inward without deformation to increase the volume of the ink liquid chamber.
When contracted, ink is not ejected, but both partition walls are
From the neutral position to the outside of the ink liquid chamber,
After expanding the volume of the ink liquid chamber, it deforms to the inside of the ink liquid chamber.
When the volume of the ink liquid chamber is contracted
To morphism, an ink jet apparatus, wherein, when ejecting the ink from both the first ink chamber and a second ink chambers adjacent to each other physician, the first
The partition walls on both sides of one ink liquid chamber are moved from the neutral position to the first
The first ink liquid chamber to expand outside the ink liquid chamber.
After supplying ink to the first ink liquid chamber,
Deforms the wall from the neutral position to the inside of the first ink liquid chamber
To shrink the volume of the first ink liquid chamber,
The second ink liquid chamber faces a partition wall between the first ink liquid chamber and the second ink liquid chamber.
To the outside of the second ink liquid chamber,
The volume of the ink liquid chamber is expanded to be
And then the partition walls are moved to the neutral position and the
The volume of the second ink liquid chamber is changed to the inside of the second ink liquid chamber.
An ink ejecting apparatus, wherein a voltage is applied to the partition wall so as to contract the ink. 2. The control means according to claim 1 , wherein said control means controls a ratio of a length L of said ink chamber to a sound velocity a in said ink in a direction L / a for expanding the volume of said ink chamber and for contracting said volume. the ink jet apparatus of claim 1 Symbol placement and applying a voltage.