JPS61164844A - Vibrator for atomizing ink - Google Patents

Abstract

PURPOSE:To allow the titled device to be miniaturized and the efficiency to be improved, by driving an ink delivery nozzle being built in a member having a clamping bolt section integrally by fundamental wave vibration. CONSTITUTION:The annular piezo electric porcelain 38a, 38b holding an electrode plate 36a therebetween and the second electrode plate 3 are positioned between a front mass 40 and a rear mass 42 and being connected by a clamping bolt 44. An ink delivery nozzle 32 is built in the tip section of the bolt 44, and the lengths of the front mass and the rear mass are same approximately, an ink flow passage 47 is formed in a center section of the bolt 44, and an ink tube 46 is connected to a taper section 48 of the bolt. In a such way, a longitudinal vibration is generated in the piezo electric porcelain 38a, 38b, and an ink column is atomized by super sound wave vibration applied to the ink column being pressed and projected, when an electric signal coinciding with a resonance frequency of said vibrator is impressed between both electrode plates 36a, 36b.

Description

[Detailed description of the invention] [Industrial application needle I? ] The present invention relates to a vibrator for atomizing ink by applying ultrasonic vibration to an ink jet nozzle in an inkjet printer. This invention relates to an ink atomization vibrator that is integrally incorporated and driven by fundamental wave vibration.

[Prior Art] An inkjet printer applies static pressure to eject liquid ink from a nozzle, forming charged ink particles during flight, and directing the ink particles to a predetermined surface of a recording medium through control electrodes This is a recording device that selectively attaches the film using the following method.

Several kilograms per inkjet head that ejects ink
There is a tie that ejects ink with a pressure of g/cd and superimposes ultrasonic vibrations. As such an ink atomization vibrator, a bolted Langevin type vibrator (hereinafter abbreviated as rBLT vibrator) is generally used. - An example of a conventional ink atomization vibrator having this product is shown in FIGS. 5 and 6. In the prior art, a structure is adopted in which an ink discharge nozzle 14 having an ink discharge port 12 is screwed onto the tip of a BLT vibrator body. BLT
The vibrator main body 10 sandwiches the electrode plate 16a. It has a structure in which two annular pressure electromagnets 18a and 18b are located between a front mass 20 and a rear mass 22 together with a second electrode plate 16b, and are connected by a cylindrical tightening bolt 24. The ink pipe 26 passes through the tightening bolt 24 and the inside of the front mass 20 and is connected to an ink tube attachment taper portion 28 formed at the rear end of the ink discharge nozzle 14. The metal members (front mass 20 and rear mass 22) are piezoelectric ceramics 18a, 18
The structure located on both sides of b is a vibrator called a Langevin type.

Here, the front mass 20 has a shape that is considerably longer in axial length than the rear mass 22 because it is connected to the rear mass 22 by a tightening bolt 24 and because the ink discharge nozzle 14 is attached to its tip. It becomes.

[Problems to be Solved by the Invention] As described above, in the prior art, a separate ink discharge nozzle 14 is screwed into the tip of the assembled BLT vibrator main body 10 (i.e., the tip of the front mass). Because of this, the axial length of the front mass increases to 100k.
Since it was not possible to create a vibrator that could be driven by a fundamental wave vibration of about Hz, we had no choice but to set the fundamental resonance frequency to about 50 kHz and design it using the second harmonic to achieve an operating frequency of about 100 kHz. Ta. Therefore, the ink atomization vibrator needs to be twice as large as the fundamental wave drive, which is a very big drawback in downsizing the device.

In addition, since the ink discharge nozzle is added after assembling the BLT vibrator, the design of the vibrator is complicated and setting the resonance frequency is difficult, and the positions of the vibration nodes are shifted, making it difficult to place the piezoelectric ceramic in the most efficient position. Because it was difficult to place, adjustments had to be made each time, making the installation process extremely cumbersome. Further, if the support position shifts, secondary vibrations occur, and extra fine particles called satellites accompany the particulate ink, which becomes noise and causes a significant deterioration in print quality.

Furthermore, since it cannot be driven with a fundamental wave as described above, it requires a high driving voltage of about 7 GV, which has the disadvantage of poor efficiency.

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and because the discharge nozzle is integrally incorporated inside the main body, it is possible to significantly reduce the size, and also to simplify the design. , since the supporting position of the vibrator can be clearly defined, Ir! It is an object of the present invention to provide an ink atomization vibrator which can realize a remarkable improvement in efficiency and can be driven with a low voltage because it can be driven with extremely large wave vibrations of strings for 2 hours.

[Means for solving the problems] The present invention, which can achieve the above objects, has B.
This is an ink atomization vibrator for an inkjet printer that uses an LT vibrator, and the ink discharge nozzle is integrated into a member having a tightening bolt part, and is configured to be driven by fundamental wave vibration. be.

Preferably, the ink discharge nozzle is formed directly at the tip of a cylindrical tightening bolt, and the front mass and the rear mass are connected by the tightening bolt.

However, in another embodiment, the tightening bolt part is integrally connected to the rear end of the front mass, the ink discharge nozzle is formed at the tip of the front mass, and the front mass is connected to the rear mass by the tightening bolt part at the rear end of the front mass. You may also adopt a configuration that does this.

[Function] With such a structure, it is possible to significantly reduce the size of the vibrator, and the vibrator can be driven with fundamental wave vibration around 100 degrees. By applying an electric signal that matches the resonance frequency of the BLT vibrator to the piezoelectric ceramic, longitudinal vibration is generated in the piezoelectric ceramic, and ultrasonic vibrations are superimposed on the pressurized ink column, so that the ink column becomes fine particles. Ru.

In addition, since the ink discharge nozzle is integrated into the BLT vibrator body, it is possible to reduce the size of the vibrator, and the position of the vibration nodes does not shift, making it possible to stabilize the support position. It becomes easier.

[Example] Hereinafter, the present invention will be explained in more detail based on the drawings. FIGS. 1 and 2 are drawings showing an embodiment of an ink atomization vibrator according to the present invention. Since it is basically a BLT resonator, there are many similarities with conventional ones.

Two annular piezoelectric ceramics 38a sandwich an electrode plate 36a.

38b is the front mass 40 together with the second electrode plate 36b.
It is located between the rear mass 42 and the rear mass 42, and is connected by a tightening bolt 44.

Therefore, in this embodiment, the member having the tightening bolt portion refers to the tightening bolt itself.

Here, the present embodiment is significantly different from the prior art in that the ink discharge nozzle 32 is incorporated into the tip of the tightening bolt 44, and that the axial lengths of the front mass 40 and the rear mass 42 are designed to be approximately equal. The point is that The tightening bolt 44 has an ink flow path 47 in its center.
is formed and is coupled to the ink tube 46 by a tapered portion 48 for attaching the ink tube at the rear end.

The piezoelectric ceramics 38a, 38b are made of titanium, lead zirconate, etc. as before, and both end surfaces maintain good flatness and parallelism, realizing good surface contact with the electrode plates 36a, 36b and the rear end surface of the front mass 40. It is supposed to be done.

As described above, in this embodiment, the front mass 40 and the rear mass 42 having approximately the same axial length are connected to the ink discharge nozzle 3.
They are connected and integrated by a tightening bolt 44 provided with 2, thereby constructing an ink atomization vibrator.

Such an ink atomization vibrator includes both electrode plates 36a,
By applying an electric signal that matches the resonance frequency of the vibrator between 36b and □, longitudinal vibration is generated in the piezoelectric ceramic plates 38a and 38b, and ultrasonic vibration is superimposed on the pressurized ink column. This makes the ink column fine particles. Although it can be considered to be similar to the conventional technique in that the piezoelectric ceramic is vertically vibrated and the ink column is turned into particles by ultrasonic waves, there is a big difference from the conventional technique in terms of the vibration mode of the vibrator. This is because the present invention uses a fundamental wave for driving.

The voltage used to drive this vibrator uses the fundamental wave to drive it efficiently, so it is possible to achieve good atomization with a voltage that is about one-fifth lower than that of conventional technology, which is about 13 to 15 V. becomes.

77 IF L Yukiko DL Mocking charm 4 post 2
÷ −. -, L -e -e A l
Since the 'L L-rear mass 42 is connected to the rear mass 42 by a separate tightening screw 44, each member has a structure that is easy to manufacture and assemble.

Next, FIGS. 3 and 4 show other embodiments of the ink atomization vibrator according to the present invention. The basic configuration is almost the same as that of the previous embodiment. Therefore, corresponding parts are given the same reference numerals, and explanations thereof will be omitted. This embodiment differs from the previous embodiments in that the front mass 60 and the tightening bolt portion 64 have an integral structure. Therefore, in this embodiment, the member having the tightening bolt portion refers to a member in which the front mass 60 and the tightening bolt portion 64 are integrated. An ink discharge nozzle 52 is formed at the center of the tip of the front mass 60, and a tightening bolt portion 64 is continuously provided from the rear end surface of the front mass 60, and an ink flow $67 is provided in the center passing through them vertically. A tapered portion 68 for attaching an ink tube is formed at the rear end of the portion 64, and the ink tube 46 is attached to the tapered portion 68. A piezoelectric ceramic 38a is provided between such a front mass 60 and a rear mass 42 similar to the above embodiment.
, the electrode plate 36a, the piezoelectric ceramic 38b, and the electrode plate 36b are located, and the tightening bolt portion G4 is screwed and coupled to the rear mass 42.

In this embodiment as well, the ink discharge nozzle 52 is integrated with the tightening bolt portion 64, and the axial lengths of the front mass 60 and the rear mass 42 are designed to be approximately equal. These points are the same as in the previous embodiment. Therefore, as is clear from a comparison between FIG. 3 and FIG. 1, the obtained ink atomized vibrator has an extremely similar external structure. Also in this embodiment, the vibrator is driven by the fundamental wave.

Since the operation of this vibrator is exactly the same as in the previous embodiment, a description thereof will be omitted.

Although the two embodiments of the present invention have been described in detail above, the present invention is not limited to only such configurations. Contrary to the second embodiment, a member in which the tightening bolt part and the rear mass are integrally formed may be used. In that case, it goes without saying that the ink discharge nozzle is assembled at the tip of the tightening bolt.

Furthermore, each of the above embodiments has a completely symmetrical structure in which the axial lengths of the front mass and rear bean are approximately equal and the vibration node is set at the center of the two piezoelectric ceramics. It may be set between the joint and the piezoelectric ceramic, and the front part of the node may be a front mass only, and the rear part may be a combination of two piezoelectric ceramics and a rear mass.

[Effects of the Invention] The present invention is an ink atomization vibrator configured as described above, and since the ink discharge nozzle is integrated into the vibrator body, it is possible to significantly reduce the size of the vibrator. Since it can be driven by the fundamental wave, efficiency can be greatly improved, and since there are no additional parts like in the past, the design of the transducer is easier, and the accurate support position can be determined easily, reducing installation and adjustment work. It has excellent effects such as being able to easily carry out.

In addition, since the driving efficiency is significantly improved, good ink atomization operation can be achieved with a low voltage of about 13 to 15 V, and significant power savings can be achieved.

Particularly in cases where a plurality of inkjet nozzles are arranged in parallel, such as in a color inkjet printer, it has excellent effects in terms of size reduction and power saving.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one embodiment of an ink atomization vibrator according to the present invention, FIG. 2 is an exploded perspective view thereof, FIG. 3 is a perspective view showing another embodiment of the present invention, and FIG. 5 is a perspective view showing an example of the prior art, and FIG. 6 is an exploded perspective view thereof. 12 = 32.52...No results 1. NeutLa
-16a, 16b, 36a, 36b-electrode plate,
18a. 18b, 38a, 38b--piezoelectric ceramic, 20,4
0°60...Front mass, 22.42-° Rear mass 24.44...Tightening bolt, 64...Tightening bolt part.

Claims (1)

[Claims] 1. A plurality of piezoelectric bodies sandwiching an electrode plate are positioned between a front mass and a rear mass and are connected by tightening bolts,
In the ink atomization vibrator having an ink discharge nozzle provided at the tip of the front mass, the ink discharge nozzle is integrally incorporated in a member having a tightening bolt portion, and is driven by fundamental wave vibration. Ink atomization vibrator. 2. The vibrator according to claim 1, wherein the ink discharge nozzle is incorporated in the tip of a tightening bolt, and the tightening bolt is screwed onto the front mass and the rear mass. 3. The member having the tightening bolt part has a structure in which the tightening bolt and the front mass are integrated, an ink discharge nozzle is built into the tip of the front mass, and the tightening bolt is screwed into the rear mass. A vibrator according to claim 1.