JPS62179948A - Vibration unit in ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To eliminate mutual interference caused by the propagation of mechanical vibration, by forming a monolithic type comb tooth shaped vibration unit having constitution such that a plurality of electromechanical converter elements each having a short strip shape are arranged to a comb tooth shaped elastomer. CONSTITUTION:A vibration unit 13 has constitution such that several comb tooth shaped electromechanical converter elements 3 are adhered and arranged onto a comb shaped elastic plate 12'. The elastic plate 3 forms a narrow part 3c at the comb tooth base part 3c of each comb tooth 3a of the elastic plate 12' of a drive part having the electromechanical converter elements 2 arranged thereto with respect to the cross-sectional area of each comb tooth 3a and also reduced in a cross-sectional area at said narrow part. By this constitution, the propagation of the vibration of the vibration unit driven by the application of a pulse is reduced at the narrow part 3c and the mutual interface between the vibration units is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration unit used in an inkjet head section of an inkjet recording apparatus.

Figure 19 is a cross-sectional configuration diagram showing an example of a conventional on-demand multi-nozzle inkjet head, and Figure 20 is a
In the figure, 1 is a nozzle, 2 is an electromechanical transducer, 3 is an elastic plate, 4 is a connecting portion, 5 is an ink flow path substrate, and 6 is a perspective view of the same.
is an ink droplet, 7 is an ink pressurized liquid chamber, 8 is an ink supply channel, 9 is an ink supply pipe, 10 is a vibration board, 11 is a diaphragm, 12 is a support part, 13 is a vibration unit, 14 is a positioning pin, The vibration unit 13 is constructed by bonding an electromechanical transducer 2 and an elastic plate 3. Channel board 5
is made of resin or the like, and the nozzle 1. Ink supply channel 8. The ink pressurized liquid chamber 7 and the like are integrally formed. The vibration substrate 10 is also made of resin or the like, and the diaphragm 11. Connecting part 4. The support portion 12 and the positioning pin 14 are integrally formed. As is well known, in the inkjet head, the diaphragm 11 is displaced by the vibration unit 13 to pressurize the ink in the ink pressurized liquid chamber 7, and the nozzle l
The vibration unit ejects ink droplets 6 to record on a recording paper (not shown), and the vibration unit has a comb-teeth shape as shown in FIG. 20, and has a multi-nozzle structure.

Therefore, in the multi-nozzle inkjet head as described above, it is more advantageous to have an integrated vibrating unit than a single unit in terms of parts cost, and it is easier to install the vibrating unit when adhering the unit and when assembling it to the head. The integrated type is also superior in terms of ease of handling, position accuracy control, etc.

However, when an integrated type is used, the degree of mutual interference between the vibration units, in which the vibration of the vibration unit driven by pulse application is mechanically propagated to other vibration units, makes it difficult to install multiple single vibration units. There is a problem that the size is larger than in the case of the comb teeth, but this is because the electromechanical transducer and the elastic plate are both integrated in the original part of the comb teeth.

Figure 20 shows an integrated comb-shaped vibration unit that has a configuration in which a plurality of rectangular electromechanical transducers are arranged on a comb-shaped elastic plate to reduce mutual interference caused by mechanical vibration. Although this has been shown to have the effect of reducing mutual interference, it is still not sufficient. In particular, when the elastic plate is made thicker, vibration propagation increases, which poses a design problem.

The present invention has been made in view of the above-mentioned circumstances, and
In particular, the aim is to eliminate mutual interference due to mechanical vibration propagation in an integrated comb-shaped vibration unit, and to enable easy processing of this integrated comb-shaped vibration unit with high yield. It is something that

(2) In order to achieve the above object, the present invention includes a large number of nozzles, a large number of ink pressurizing liquid chambers corresponding to each nozzle, and a vibration unit that changes the volume of the ink pressurizing liquid chamber. The ink pressurized liquid chamber has a small wall (a part of the wall is formed of an elastic body, and the elastic body is displaced by the vibration unit to change the volume of the ink pressurized liquid chamber; By,
In the inkjet recording device configured to eject ink droplets from the nozzle, the vibration unit includes a comb-shaped elastic plate and a strip-shaped electromechanical transducer arranged at each comb-teeth part of the comb-shaped elastic plate. and at least a part of the comb-like elastic plate between the comb-teeth portions has a narrow portion having a cross-sectional area smaller than the cross-sectional area of the drive portion in which the electromechanical transducer element is disposed. The comb-like elastic plate is integrated, or the vibration unit includes an elastic plate and a rectangular electromechanical transducer disposed on the elastic plate, and the elastic plate is supported. the elastic plate is joined to the body, and the elastic plate has an end face facing the drive unit that has a smaller area than the cross-sectional area of the drive unit in which the electromechanical transducer is disposed, or The vibration unit includes a comb-shaped elastic plate and a rectangular electromechanical transducer arranged on each comb-shaped part of the comb-shaped elastic plate. It is characterized by the provision of vibration suppressing material. below,
An explanation will be given based on an example of the present invention.

FIG. 1 is a cross-sectional configuration diagram for explaining one embodiment of an inkjet head according to the present invention, and FIG. 2 is a perspective view (however, a perspective view when the elastic plate shown in FIG. 3 is used). In the figure, parts having the same functions as those in FIGS. 19 and 20 are given the same reference numerals as in FIGS. 19 and 20. According to the present invention, the vibration unit 13 has a structure in which several comb-teeth electromechanical transducers 3 are bonded and disposed on a comb-teeth-shaped elastic plate 12''.

3 to 7 show the elastic plate 3 shown in FIG. 1, respectively.
(A) is a plan view, and (B) is a plan view in each figure.
) Figure is a sectional view taken along the line B-B of Figure (A), and Figure (C) is a sectional view taken along the line CC of Figure (A).

Accordingly, in the present invention, the elastic plate 3 has a narrow portion at the comb teeth root portion 3c with respect to the cross-sectional area of each comb tooth 3a of the elastic plate 3 of the drive unit in which the electromechanical transducer element 2 is disposed. Therefore, the cross-sectional area is also small, and as a result, the propagation of vibrations of the vibration units driven by pulse application is reduced in the narrow portion 3c, and mutual interference between the vibration units is eliminated. In addition, the third
In the embodiments shown in the figures to FIG. 6, the cross-sectional area of the comb tooth root portion 3c (Fig. (C)) is smaller than the cross-sectional area of the comb tooth portion 3a of the drive section (Fig. (B)). and these elastic plates 3
is made of metal and can be easily processed by etching, pressing, etc. In addition, FIG. 7 shows the pinched portion 3 of the comb tooth base.
By making the thickness of C thinner than the thickness of the comb tooth portion 3a,
The cross-sectional area of the comb root portion 3C (Figure (C)) is made smaller than the cross-sectional area of the comb tooth portion (Figure (B)), which can be easily processed by half etching or the like.

In addition, as for the electrode of the electromechanical transducer 2, since the elastic plate 3 is integrated with the elastic plate 3 through the small part, it is possible to remove the electrode from the elastic plate as a common electrode. can.

FIG. 8 is a plan view of the case where the support portion 12 shown in FIG. 1 is separated into a comb-like support body 12'.

As is clear from the above description, according to the above embodiment,
Mutual interference due to mechanical vibration can be reduced by forming an integrated comb-like vibration unit in which a plurality of rectangular electromechanical transducers are arranged on a movable tooth-like elastic body. In addition, by configuring as described above,
An integrated comb-shaped vibration unit can be easily fabricated.

FIG. 9 is a cross-sectional view for explaining another embodiment of the inkjet head according to the present invention, and FIG. 10 is a perspective view thereof. Parts having similar functions are provided with the same reference numerals as in FIG. 2 and FIG.

FIG. 11 is a plan view of the elastic plate 3 shown in FIGS. 9 and 10 during the processing process, and FIG. 12 is a plan view of the support 12'', both of which are made of metal and are not subjected to etching or press processing. Processed by etc.

The elastic plate 3 has a driving part 3a, a positioning hole 3b, and a pinching part 3c, as in the previous embodiment. Further, the support body 12° has comb teeth similar to the elastic plate 3, and the vibration of the vibration unit is supported at the tip of each comb tooth. The elastic plate 3 is adhered to a predetermined position on the support 12', and then the elastic plate is easily cut along the line A-A of the narrow part at the narrow part 3c by means of a laser, press, etc. It is processed as shown in FIG. 13, and an electromechanical transducer is adhesively arranged at a predetermined position and bonded onto the head.

As a result, the cross-sectional area facing the driving part becomes smaller than the cross-sectional area of the driving part. In the series of processing described above, the elastic plate can be handled as a single piece, so handling is easy and position accuracy control is also easy. Furthermore, the cut portion also has a small cross section, which can reduce the generation of heat and strain.

FIGS. 14(II) to (III) are views showing processing examples of the elastic plate 3 as described above, in which FIG. 14(A) is a plan view before processing, FIG. 14(B) is a plan view after processing, and FIG. C) The figure shows the cross-sectional shape of the processed part. By cutting along the dotted line in figure (A), it is possible to form the structure shown in figure (B) and the end face shape as shown in figure (C).

As is clear from the above description, according to the above embodiment,
In other words, the elastic plate is completed by forming a comb-shaped vibration unit that is integrated with a support body in which a plurality of rectangular electromechanical transducers are arranged on a plurality of elastic bodies. Since the vibration units are completely separated, 1JiTh of the vibration unit does not propagate through the elastic plate, and mutual interference due to mechanical vibration can be reduced. Moreover, by adopting the above-mentioned configuration, an integrated comb-shaped vibration unit can be easily manufactured.

FIG. 15 is a cross-sectional view for explaining another embodiment of the present invention, and FIG. 16 is a perspective view. In this embodiment, the diaphragm 3 is attached to the support part 12 by a vibration suppression plate 15. There is.

In FIG. 17, (A) is a plan view of the elastic plate 3 shown in FIG. 15, (B) and (Bo) are perspective views of the vibration suppressing material 15, and FIG. (Bo) An example using the vibration suppressing material 15 shown in the figure is shown.

In this embodiment, the comb-shaped elastic plate 3 is provided with mounting holes 3a at the roots of each comb tooth, while the vibration suppressing material 15 is provided with mounting holes 3a at positions corresponding to the mounting holes. bottle 15
A is provided. This joining pin 15a is attached to the mounting hole 3a.
By press-fitting the vibration suppressing material 15 into the comb-like elastic plate 13
placed above. The vibration suppressing material 15 is made of a high-density metal such as lead. As mentioned above, the mechanical propagation of the vibration of the driven vibrating unit to other vibrating units is due to the original common portion of the comb teeth. Therefore, by firmly joining a member with a relatively large mass to the vibrating unit at this location, the vibration will be rapidly attenuated, and the vibration will not be mechanically propagated between the vibrating units. disappears. Here, the overall condition of the comb-like elastic plate and the vibration suppressing material is very important, and it is desirable that vibrations are directly transmitted between them so that they are integrated.

FIG. 18 is a diagram showing another example of the comb-like elastic plate 3 and the vibration suppressing material 15. In the above embodiment, the pre-formed vibration suppressing material 15 was installed by press-fitting into the comb-like elastic plate 3, but for example, by soldering solder into the mounting holes of the comb-like elastic plate. It is also possible to suppress vibrations. .

As is clear from the above description, according to the above embodiment,
In an integrated comb-shaped vibration unit having a configuration in which a plurality of rectangular electromechanical transducers are arranged on a comb-shaped elastic body, by disposing a vibration suppressing material on the comb-shaped diaphragm, Mutual interference due to mechanical vibration can be reduced.

Moreover, by adopting the above-mentioned configuration, an integrated comb-shaped vibration unit can be easily manufactured.

As is clear from the above explanation, according to the present invention, (a) an integrated comb-shaped vibration unit can be easily fabricated.

(b) Mutual interference due to mechanical vibrations can be reduced by creating an integrated comb-shaped vibration unit with a configuration in which a plurality of rectangular electromechanical transducers are arranged on a comb-shaped elastic body. I can do it.

(c) Mutual interference due to mechanical vibration is achieved by forming an integrated comb-shaped vibration unit via a support body in which a plurality of rectangular electromechanical transducers are arranged on a plurality of elastic bodies. can be reduced.

(d) In an integrated comb-shaped vibration unit having a configuration in which a plurality of rectangular electromechanical transducers are arranged on a comb-shaped elastic body, a vibration suppressing material is arranged on the comb-shaped diaphragm. By doing so, mutual interference due to mechanical vibration can be reduced.

There are advantages such as

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view for explaining one embodiment of an inkjet head according to the present invention, FIG. 2 is a perspective view, and FIGS. 3 to 7 are respectively views of the elastic plate 3 shown in FIG. 8 is a plan view of the support plate 12'; FIG. 9 is a sectional view for explaining another embodiment of the inkjet head according to the present invention; FIG. 1O is a perspective view; FIG. 11 is a plan view of the elastic plate 3 shown in FIG. 9 during processing;
12 is a plan view of the support plate 12', FIG. 13 is a plan view of the elastic plate 3, FIGS. 14 (1) to (III) are views showing processing examples of the elastic plate 3, and FIG. 16 is a perspective view, and FIGS. 17 and 18 show the elastic plate 13 and vibration suppressor shown in FIG. 15, respectively. FIG. 19 is a sectional view showing an example of a conventional inkjet head, and FIG. 20 is a perspective view thereof. 1... Nozzle, 2... Electromechanical conversion element, 3...
elastic board. 10... Vibration board, 12... Support part, 12゛...
Support plate. 13... Vibration unit, 14... Positioning pin, 1
5... Vibration suppressing material.

Claims (4)

[Claims] (1) It has a large number of nozzles, a large number of ink pressurizing liquid chambers corresponding to each nozzle, and a vibration unit that changes the volume of the ink pressurizing liquid chamber, and the ink pressurizing liquid chamber is At least a part of the wall is formed of an elastic body, and the elastic body is displaced by the vibration unit to change the volume of the ink pressurized liquid chamber, thereby ejecting ink droplets from the nozzle. In the recording device, the vibration unit includes a comb-shaped elastic plate and a strip-shaped electromechanical transducer arranged on each comb-shaped part of the comb-shaped elastic plate, and the comb-shaped elastic plate The comb-shaped elastic plate is integrated with at least a portion between each of the comb-teeth portions having a narrow portion having a cross-sectional area smaller than the cross-sectional area of the drive portion in which the electromechanical transducer is disposed. A vibration unit in an inkjet recording device characterized by: (2) It has a large number of nozzles, a large number of ink pressurizing liquid chambers corresponding to each nozzle, and a vibration unit that changes the volume of the ink pressurizing liquid chamber, and the ink pressurizing liquid chamber is At least a part of the wall is formed of an elastic body, and the elastic body is displaced by the vibration unit to change the volume of the ink pressurized liquid chamber, thereby ejecting ink droplets from the nozzle. In the recording device, the vibration unit includes an elastic plate and a rectangular electromechanical transducer disposed on the elastic plate, the elastic plate is joined to a support, and the elastic plate A vibration unit for an inkjet recording apparatus, characterized in that an end surface facing the drive section has a smaller area than a cross-sectional area of the drive section in which an electromechanical transducer is disposed. (3) It has a large number of nozzles, a large number of ink pressurizing liquid chambers corresponding to each nozzle, and a vibration unit that changes the volume of the ink pressurizing liquid chamber, and the ink pressurizing liquid chamber is At least a part of the wall is formed of an elastic body, and the elastic body is displaced by the vibration unit to change the volume of the ink pressurized liquid chamber, thereby ejecting ink droplets from the nozzle. In the recording device, the vibration unit includes a comb-shaped elastic plate and a strip-shaped electromechanical transducer arranged on each comb-shaped part of the comb-shaped elastic plate, and the comb-shaped elastic plate A vibration unit in an inkjet recording device, characterized in that a metal vibration suppressing material is disposed on top of the vibration unit. (4) The inkjet recording apparatus according to claim (3), wherein comb teeth of the vibration suppressing material are arranged to correspond to each comb tooth of the comb-like elastic plate. vibration unit.