JPH06218934A - Droplet ejector manufacturing method and droplet ejector - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the processing speed in the cutting of the grooves that make up the ink flow path. [Structure] A plurality of grooves 8 are formed in a piezoelectric ceramic plate 27 by cutting by rotating a diamond cutting disk. The grooves 8 are parallel and have the same depth. Then, the metal electrodes 13 are formed on the upper half of both side surfaces of the groove 8. Next, the conductive paste 26 is embedded in the groove 8 by the dispenser 25. Therefore, the groove 8
The metal electrode 13 on one side and the metal electrode 13 on the other side are electrically connected by the conductive paste 26.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a droplet ejecting method for ejecting ink in an ink flow passage from a nozzle communicating with the ink flow passage by changing the volume of the ink flow passage using a piezoelectric transducer. It relates to the device.

[0002]

2. Description of the Related Art Conventionally, as this type of droplet ejecting apparatus,
For example, there is one described in JP-A-2-150355. The schematic configuration will be described below with reference to the drawings.

As shown in FIG. 5, the ink jet printer head 1 is composed of a piezoelectric ceramic plate 2, a cover plate 3, a nozzle plate 31, and a substrate 41.

The piezoelectric ceramic plate 2 is made of a lead zirconate titanate (PZT) -based ceramic material having ferroelectricity. The piezoelectric ceramic plate 2 is polarized in the polarization direction 5. Next, as shown in FIG.
As shown in, the diamond cutting disk 30 is rotated to perform cutting. During this cutting, the cutting direction of the diamond cutting disk 30 is 30A,
It is changed to 30B and 30C.

The groove 8 is formed by the cutting direction 30A of the diamond cutting disk 30. The width of the groove 8 is 7
The thickness is about 0 to 100 μm, and the depth is 300 to 500 μm in order to obtain a sufficient volume change of the ink flow path for ejecting an ink droplet, to the piezoelectric ceramic plate 2 having a thickness of 1 mm. It is about a meter. Subsequently, the cutting direction is changed from 30A to 30B, and the depth of cutting is changed. Then, the cutting direction is changed from 30B to 30C to form the shallow groove 16. The depth of the shallow groove 16 is about 10 to 50 micrometers.

As shown in FIG. 5, a plurality of grooves 8 and shallow grooves 16 are formed in the piezoelectric ceramic plate 2 cut in this way. The grooves 8 are of the same depth and are parallel. The shallow grooves 16 are formed near the one end surface 15 of the piezoelectric ceramic plate 2. Further, the side wall 11 which is the side surface of the groove 8 is polarized in the direction of arrow 5 by the polarization treatment.

Further, metal electrodes 13 and 9 are formed on the side surfaces of the groove 8 and the inner surface of the shallow groove 16 by a vapor deposition method. As shown in FIG. 7, when the metal electrodes 13 and 9 are formed, the piezoelectric ceramic plate 2 is tilted with respect to the direction of vapor emission from a target or vapor deposition source (not shown). When the vapor is discharged, the groove 8 is formed by the shadow effect of the side wall 11.
The metal electrodes 13, 9 and 10 are formed on the upper half of the side surface, the inner surface of the shallow groove 16 and the upper surface of the side wall 11. Next, the piezoelectric ceramic plate 2 is rotated 180 degrees, and the metal electrodes 13, 9, 10 are formed in the same manner. After this, the side wall 1
The unnecessary metal electrode 10 formed on the upper surface of 1 is removed by lapping or the like. Thus, the metal electrodes 13 formed on both side surfaces of the groove 8 are electrically connected by the metal electrodes 9 formed on the inner surface of the shallow groove 16.

Next, the cover plate 3 shown in FIG. 5 is made of a ceramic material, a resin material or the like.
The cover plate 3 has an ink inlet 21 and a manifold 22 formed by grinding or cutting. Then, the surface of the piezoelectric ceramic plate 2 on the groove 8 side and the manifold 22 of the cover plate 3
The surface on the processing side is adhered by an adhesive 4 such as an epoxy adhesive (see FIG. 9). Therefore, in the ink jet printer head 1, the upper surface of the groove 8 is covered, and a plurality of ink flow paths having lateral intervals are formed. Ink is filled in all the ink flow paths.

To the end faces of the piezoelectric ceramic plate 2 and the cover plate 3, a nozzle plate 31 having a nozzle 32 provided at a position corresponding to the position of each ink flow path is adhered. The nozzle plate 31 is formed of a plastic such as polyalkylene (for example, ethylene), terephthalate, polyimide, polyetherimide, polyetherketone, polyethersulfone, polycarbonate, or cellulose acetate.

A substrate 41 is adhered to the surface of the piezoelectric ceramic plate 2 opposite to the processed side of the groove 8 with an epoxy adhesive or the like. Its substrate 41
The conductive layer pattern 42 is formed at a position corresponding to the position of each ink flow path. The conductive layer pattern 42
And the metal electrode 9 on the bottom surface of the shallow groove 16 are connected by a conductive wire 43 by known wire bonding or the like.

Next, the structure of the control unit will be described with reference to FIG. 8 which is a block diagram of the control unit. The conductive layer patterns 42 formed on the substrate 41 are individually connected to the LSI chip 51. The clock line 52, the data line 53, the voltage line 54, and the ground line 55 are also LS.
It is connected to the I-chip 51. The LSI chip 51 is
Based on the continuous clock pulse supplied from the clock line 52, it is determined from which nozzle 32 the ink droplet should be ejected according to the data appearing on the data line 53. Then, the voltage V of the voltage line 54 is applied to the pattern 42 of the conductive layer electrically connected to the metal electrode 13 (FIG. 9) in the driven ink flow path 12 (FIG. 9). In addition, the metal electrode 1 other than the driven ink channel 12
A voltage of 0 V on the ground line 55 is applied to the pattern 42 of the conductive layer connected to 3.

Next, the operation of the ink jet printer head 1 will be described with reference to FIGS.

The LSI chip 51 causes the ink flow path 12 of the ink jet printer head 1 to follow the required data.
It is determined that ink is ejected from b. Then, a positive drive voltage V is applied to the metal electrodes 13e and 13f via the conductive layer pattern 42 corresponding to the ink flow path 12b and the metal electrode 9, and the metal electrodes 13d and 13g are grounded. As shown in FIG. 10, the side wall 11b has an arrow 14b.
Driving electric field is generated in the direction of arrow 14c on the side wall 11c.
A driving electric field in the direction of is generated. Then, the driving electric field direction 1
Since the polarization directions 4b and 14c are orthogonal to each other, the side walls 11b and 11c are rapidly deformed in the inward direction of the ink flow path 12b due to the piezoelectric thickness sliding effect. Due to this deformation, the volume of the ink flow path 12b is reduced, the ink pressure is rapidly increased, a pressure wave is generated, and an ink droplet is ejected from the nozzle 32 (FIG. 5) communicating with the ink flow path 12b.

When the application of the drive voltage V is stopped,
Since the side walls 11b and 11c gradually return to the positions before the deformation (see FIG. 9), the ink pressure in the ink flow path 12b gradually decreases. Then, ink is supplied from the ink supply port 21 (FIG. 5) through the manifold 22 (FIG. 5) into the ink flow path 12b.

In this way, in order to eject ink droplets,
The central portions of the side walls 11 on both sides of the groove 8 are simultaneously deformed toward the inside of the groove 8. Therefore, the metal electrode 13 is formed on the upper half of the side wall 11, and the side walls 11 on both sides of the groove 8 are simultaneously deformed. Side walls 11 on both sides of the groove 8
In order to simultaneously deform the metal electrodes 1 on both sides of the groove 8.
A metal electrode 9 for electrically connecting 3 is provided, and a voltage is applied to the metal electrode 9. Therefore, the shallow groove 16 is formed in order to form the metal electrode 9 for electrically connecting the metal electrodes 13 formed on the upper half of both sides of the groove 8.

[0016]

However, in the above-mentioned liquid droplet ejecting apparatus, since the groove 8 is formed and the shallow groove 16 is formed, the processing direction of the diamond cutting disk 30 is changed during cutting. Therefore, there is a drawback that the cutting control becomes complicated and the cutting speed becomes slow. Since a plurality of grooves 8 and shallow grooves 16 are formed on the piezoelectric ceramic plate 2, mass production of such a droplet ejecting device deteriorates productivity due to the delay in cutting speed.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide a method of manufacturing a droplet jetting apparatus and a droplet jetting apparatus which have a high production speed and are excellent in mass production. To do.

[0018]

To achieve this object, in the present invention, a piezoelectric transducer is used to change the volume of the ink flow passage so that the ink in the ink flow passage is transferred to the ink flow passage. In a method of manufacturing a droplet ejecting device that ejects from a communicating nozzle, a step of forming a groove in the piezoelectric transducer in order to configure the ink flow path, and a voltage for changing the volume of the ink flow path A step of forming drive electrodes to be applied on both sides of the groove, and a drive electrode on one side of the groove and a drive electrode on the other side of the groove so as to simultaneously apply voltage to the drive electrodes provided on both sides of the groove. And a step of forming a conductive material in the groove in order to electrically connect with the groove.

Further, in the liquid droplet ejecting apparatus for ejecting the ink in the ink flow path from the nozzle communicating with the ink flow path by changing the volume of the ink flow path using the piezoelectric transducer, the piezoelectric transducer Provided on both side surfaces of the groove, a groove forming the ink flow path, a drive electrode formed on both side surfaces of the groove and to which a voltage is applied to change the volume of the ink flow path. In order to apply a voltage to the drive electrodes simultaneously, a conductive material is formed in the groove and electrically connects the drive electrode on one side surface of the groove and the drive electrode on the other side surface.

Further, the conductive material is filled in the end portion of the groove opposite to the nozzle.

[0021]

According to the present invention having the above-mentioned structure, the droplets ejecting the ink in the ink flow passage from the nozzle communicating with the ink flow passage by changing the volume of the ink flow passage using the piezoelectric transducer. In the method for manufacturing an ejection device, a groove is cut in the piezoelectric transducer to form the ink flow path, and a drive electrode to which a voltage is applied in order to change the volume of the ink flow path is formed in the groove. In order to apply a voltage to the drive electrodes formed on both sides of the groove on both sides of the groove at the same time, a conductive electrode is formed to electrically connect the drive electrode on one side of the groove and the drive electrode on the other side. A substance is formed in the groove.

Further, in the liquid droplet ejecting apparatus for ejecting the ink in the ink flow path from the nozzle communicating with the ink flow path by changing the volume of the ink flow path using the piezoelectric transducer, the piezoelectric transducer The drive electrodes formed on both sides of the groove forming the ink flow path change the volume of the ink flow path when a voltage is applied, and the conductive material is provided on both side surfaces of the groove. In order to apply a voltage to the driving electrodes at the same time, the driving electrodes formed on the groove are electrically connected to the driving electrodes on one side of the groove and the driving electrodes on the other side.

Further, the conductive substance filled in the end portion of the groove on the side opposite to the nozzle does not discharge ink from the end portion.

[0024]

An embodiment of the present invention will be described in detail below with reference to the drawings. For convenience, the same parts as those of the conventional example and the equivalent parts are given the same reference numerals,
Detailed description thereof will be omitted.

The piezoelectric ceramic plate 27 shown in FIG.
Is lead zirconate titanate (PZT) with ferroelectricity
Manufactured from ceramic materials. The piezoelectric ceramic plate 27 is a plate having a thickness of about 1 mm which is polarized in the direction of arrow 5. Further, a plurality of grooves 8 are formed on the piezoelectric ceramic plate 27 by cutting by rotating the diamond cutting disk 30 (see FIG. 6) described above. The grooves 8 are parallel,
And it is the same depth. The grooves 8 have a depth of about 400 μm, a width of about 80 μm, and a pitch of 169 μm.

Then, as described above, the metal electrodes 13 and 10 are formed on the upper halves of both side surfaces of the groove 8 and the upper surfaces of the side walls 11. Aluminum is used for the metal electrodes 13 and 10.
Nickel or the like is used.

Next, as shown in FIG. 3, the conductive paste 2
6 is embedded in the groove 8 by the dispenser 25. At this time, a plurality of dispensers 25 are provided, and the dispensers 25 are arranged above each groove 8. Then, heat (100 degrees) is applied to the conductive paste 26 by a device (not shown), and the conductive paste 26 is solidified by the heat. As the conductive paste 26, gold paste, silver paste, copper paste or the like is used. The conductive paste 26 is formed near the end portion 15 (FIG. 1) of the piezoelectric ceramic plate 27. In addition, the conductive paste 26 is formed in the groove 8
Meets all the depth of. Then, the conductive paste 26
And the metal electrode 10 on the upper surface of the side wall 11 are removed by lapping or the like.

Therefore, the metal electrode 13 on one side of the groove 8 and the metal electrode 13 on the other side are electrically connected by the conductive paste 26. Therefore, when a voltage is applied to the conductive paste 26, a voltage is simultaneously applied to the metal electrodes 13 on both sides of the groove 8 through the conductive paste 26, and at the same time, the sidewalls 11 on both sides of the groove 8 are formed as described above. The ink droplets are ejected by being deformed in the inner direction of 8. Further, since the groove 8 is closed by the conductive paste 26 at the end 15 of the piezoelectric ceramic plate 27, the ink is discharged from the end 15 even when the ink flow path 12 (see FIG. 9) is filled with the ink. Never.

Then, the surface of the piezoelectric ceramic plate 27 on the groove 8 side and the manifold 22 of the cover plate 3
The surface on the processing side is adhered by an adhesive 4 such as an epoxy adhesive (see FIG. 9). Therefore, the ink jet printer head 1 is formed with a plurality of ink flow paths 12 (see FIG. 9) which cover the upper surfaces of the grooves 8 and are laterally spaced from each other. Then, the ink is filled in all the ink flow paths 12.

Next, a nozzle plate 31 having nozzles 32 provided at positions corresponding to the positions of the ink flow paths 12 is adhered to the end faces of the piezoelectric ceramic plate 27 and the cover plate 3.

Then, the substrate 41 is adhered to the surface of the piezoelectric ceramic plate 27 opposite to the processed side of the groove 8 with an epoxy adhesive or the like. A pattern 42 of a conductive layer is formed on the substrate 41 at positions corresponding to the positions of the ink flow paths. The pattern 42 of the conductive layer and the conductive paste 26 are connected by a conductive wire 43 by wire bonding.

Next, the structure of the ink jet printer will be described with reference to FIG. The ink jet printer head 1 and the ink container 61 described above are joined so that the ink introducing port 21 (FIG. 1) of the ink jet printer head 1 and the inside of the ink container 61 communicate with each other. When the ink inside the ink container 61 is consumed, the ink container 61 is removed from the carriage 62 and replaced with a new one. The carriage 62 reciprocates on the slider 63, and the inkjet printer head 1 prints and records on the recording paper 66 held by the platen 64. The recording paper 66 is moved by the paper feed rollers 65a and 65b in a direction orthogonal to the moving direction of the carriage 62. As a result, the inkjet printer head 1 can print and record on the entire surface of the recording paper 66.

In such an ink jet printer, when ink droplets are ejected, small ink droplets are generated, and a part of them is attached to the ink ejection surface of the ink jet printer head 1. If left unattended, ink gradually accumulates on the ink ejection surface, making it impossible to eject ink droplets. Therefore, the carriage 62 moves to the leftmost non-printing area for a proper period after the printing is completed or when the use of the inkjet printer is completed. At this time, the ink ejection surface is engaged with the wiper member 68 provided on the support member 69 fixed to the non-printing area and formed of resin or fiber such as cotton, and moves to the left. By this sliding operation, the ink droplets adhering to the ink ejection surface are removed by the wiper member 68. When a large amount of ink adheres to the wiper member 68, the wiper member 68 is replaced with a new one.

A moving means for moving the wiper member 68 is provided, and the wiper member 68 is provided on the surface of the nozzle plate 31 of the ink jet head 1 moved to the non-printing area.
May be moved and slid.

As described above, since the grooves 8 having a constant depth are formed in the piezoelectric ceramic plate 27,
Easy control in cutting and high processing speed.
Therefore, such an inkjet printer head 1
High productivity in mass production.

In this embodiment, the conductive paste 26 fills the entire depth of the groove 8 of the piezoelectric ceramic plate 27. However, even if the conductive paste 26 does not fill the entire depth of the groove 8, the metal on both side surfaces of the groove 8 may be filled. The electrodes 13 may be formed so as to be electrically connected. For example, the conductive paste 26 may be formed up to the sixth minute of the depth of the groove 8. However, in this way, when the ink flow path 12 (see FIG. 9) is filled with the ink, the piezoelectric ceramic plate 27 is formed by the conductive paste 26.
Since the effect of not discharging the ink from the end portion 15 of the groove 8 cannot be obtained, a member for closing the end portion 15 of the groove 8 is required.

Further, in the present embodiment, the metal electrode 13 on one side of the groove 8 and the metal electrode 13 on the other side are electrically connected by the conductive paste 26, but one side of the groove 8 is formed by the conductive rubber. The metal electrode 13 and the metal electrode 13 on the other side surface may be electrically connected.

The present embodiment can be modified without departing from the gist of the present invention. For example, the pitch, width, and depth of the grooves 8 formed in the piezoelectric ceramic plate 27 are not specified and are arbitrary.

[0039]

As is apparent from the above description, according to the present invention, in order to form an ink flow path filled with ink, a groove is formed in the piezoelectric transducer and the volume of the ink flow path is changed. Drive electrodes to which a voltage is applied are formed on both side surfaces of the groove, and a drive electrode on one side surface of the groove is formed to simultaneously apply a voltage to the drive electrodes provided on both side surfaces of the groove. Since the conductive material that electrically connects to the drive electrode on the other side surface is formed in the groove, the cutting speed of the groove is high. Therefore, the manufacturing speed of the liquid droplet ejecting apparatus is high, and it is effective in mass production. Further, if the end portion of the groove on the side opposite to the nozzle from which the droplet is ejected is filled with the conductive substance, there is an effect that the ink is not discharged from the end portion.

[Brief description of drawings]

FIG. 1 is a perspective view showing the configuration of an inkjet printer head according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a forming process of the piezoelectric ceramic plate of the embodiment.

FIG. 3 is a cross-sectional view showing a process of forming a conductive paste on the piezoelectric ceramic plate of the above embodiment.

FIG. 4 is a perspective view showing a schematic configuration of an inkjet printer including the inkjet printer head of the embodiment.

FIG. 5 is a perspective view showing a configuration of a conventional inkjet printer head.

FIG. 6 is an explanatory view showing a cutting process of a conventional piezoelectric ceramic plate.

FIG. 7 is an explanatory view showing an electrode forming process of a conventional piezoelectric ceramic plate.

FIG. 8 is an explanatory diagram showing a control unit of a conventional inkjet printer head.

FIG. 9 is a cross-sectional view of a conventional inkjet printer head.

FIG. 10 is an explanatory diagram showing an operating state of a conventional inkjet printer head.

[Explanation of symbols]

 8 Groove 12 Ink Flow Path 13 Metal Electrode 26 Conductive Paste 27 Piezoelectric Ceramic Plate 32 Nozzle

Claims (3)

[Claims] 1. A liquid droplet ejecting apparatus for ejecting ink in an ink flow path from a nozzle communicating with the ink flow path by changing the volume of the ink flow path using a piezoelectric transducer. Forming a groove in the piezoelectric transducer to form a path; forming drive electrodes to which a voltage is applied on both side surfaces of the groove in order to change the volume of the ink flow path; A conductive material is formed in the groove in order to electrically connect the drive electrode on one side of the groove and the drive electrode on the other side of the groove in order to simultaneously apply a voltage to the drive electrodes provided on both sides of the groove. A method of manufacturing a liquid droplet ejecting apparatus, comprising: 2. A liquid droplet ejecting apparatus for ejecting ink in the ink flow path from a nozzle communicating with the ink flow path by changing the volume of the ink flow path using the piezoelectric transducer. A groove that forms the ink flow path, a drive electrode that is formed on both side surfaces of the groove and to which a voltage is applied to change the volume of the ink flow path, and a drive electrode that is provided on both side surfaces of the groove. In order to apply a voltage to the driven electrodes at the same time, a conductive material is formed in the groove and electrically connects the driving electrode on one side surface of the groove and the driving electrode on the other side surface. And a liquid droplet ejecting device. 3. The liquid droplet ejecting apparatus according to claim 2, wherein the conductive material is filled in an end portion of the groove opposite to the nozzle, and ink is not discharged from the end portion.