JP2823920B2 - Ink jet recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an ink jet recording apparatus, and more particularly, to a head section of an ink jet recording apparatus. For example, it is applied to various recording devices.

2. Description of the Related Art Japanese Patent Application Laid-Open No. 60-90770 is a known document describing the prior art according to the present invention. This discloses a head made of a rigid member that provides a piezoelectric element on a vibration plate and holds it rigidly, and instead of deformation by a piezoelectric strain constant perpendicular to the polarization direction, deformation by the same piezoelectric strain constant as the polarization direction is disclosed. By using this, the pressurizing chambers can be arranged at a high density, and electrical connection is facilitated.

FIG. 5 is a view showing a head portion of a conventional ink jet recording apparatus, in which 21 is a rigid member, 22 is a piezoelectric element, 23 is a groove, 24 and 28 are electrodes, 25 is a pressurizing chamber, 26 is a nozzle, 27 is an ink supply path, and 29 is a substrate. This is a head on which a substrate 29, a piezoelectric element 22, a pressure chamber forming member, and the like are stacked.

FIG. 6 shows an example in which heads are stacked for higher density printing on this head. One of the disadvantages of this structure is that it has a large number of parts. Another drawback is that each component requires high accuracy in order to ensure nozzle position accuracy between the two heads. That is, main components (substrate, piezoelectric element, diaphragm, and pressure chamber forming member)
Are required, and the assembling time is similarly increased. In addition, nozzle position accuracy is determined by the sum of the thicknesses of the substrate, piezoelectric element, and diaphragm, the upper and lower unit assembly processes, and the accuracy of the pressurizing chamber forming members. Met.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an ink jet recording apparatus that reduces the number of parts, shortens assembly time, and achieves low cost and high accuracy. It is a thing.

Configuration In order to achieve the above object, according to the present invention, a piezoelectric element is laminated on a substrate, a plurality of parallel slits are formed in the piezoelectric element, and a plurality of slits are formed corresponding to the protrusions of each piezoelectric element between the slits. One of the pressurized chambers is connected to the nozzle, the other is connected to the ink supply unit, and the piezoelectric element applies an electric field in a direction perpendicular to the longitudinal direction of the slit and the array direction. In an ink jet recording apparatus for ejecting ink from a nozzle by displacing a thickness in the same direction as an electric field, the piezoelectric element is divided into a plurality of blocks in a longitudinal direction of a slit, and a pressure chamber and an ink supply section in a pressure chamber forming member. This also corresponds to that, and the ink is ejected from the nozzle in the pressure chamber forming member.
Hereinafter, a description will be given based on examples of the present invention.

FIG. 1 is a configuration diagram for explaining an embodiment of an ink jet recording apparatus according to the present invention, wherein 1 is a substrate, 2
Is a piezoelectric element, 3 is a slit, 4 is a convex part of the piezoelectric element, 5 is a pressure chamber, 6 is a nozzle, 7 is an ink supply section, 8 is a diaphragm,
9 is a pressure chamber forming member, 10 is a nozzle plate, and 15 is a nozzle-side flow path. A substrate 1, a piezoelectric element 2, a vibration plate 8, a pressure chamber forming member 9, and a nozzle plate 10 are laminated.

2 (a) and 2 (b) are plan views of the pressure chamber forming member as viewed from the direction of the diaphragm. The pressurizing chamber 5, the ink supply unit 7, the nozzle-side flow path 15, and the like are composed of two blocks. Figure (b)
As described above, the pressurizing chamber 5 may be separated in a stepwise manner. However, the driving individual electrodes of the piezoelectric element 2 also need to be separated.

FIG. 3 is a perspective view of a slit-processed piezoelectric element. Although the diaphragm 8 may be used as shown in FIG. 1, the slit may be filled with an elastic body and the slit may be laminated without using the diaphragm.

4 (a) and 4 (b) are configuration examples of electrodes of the piezoelectric element, and are sectional views in the same direction as FIG. FIG. 4 (a) shows an example of a single-layer piezoelectric element, in which the common electrode 12 is provided on the lower surface (substrate side), and the individual electrodes 11 are provided on the upper surface so as to be separated substantially at the center. This may be upside down.

FIG. 4 (b) shows an example of the configuration of the electrodes in the case of a laminated piezoelectric element, where 13 is an individual internal electrode and 14 is a common internal electrode.
By using this, low electricity can be achieved, but two piezoelectric elements are required. It is better to insulate both parts where they may come into contact with the ink.

Advantages As is clear from the above description, according to the present invention, the number of parts can be reduced to about half that of the conventional example, and the assembling time can be reduced.

Moreover, since the positional accuracy between the nozzles is determined only by the partial accuracy of the nozzle plate, there is no particular need for other parts or the accuracy of assembly.

As described above, the cost can be reduced, and the nozzle position accuracy can be improved.

[Brief description of the drawings]

FIG. 1 is a structural view for explaining an embodiment of an ink jet recording apparatus according to the present invention, and FIGS. 2 (a) and 2 (b).
Fig. 3 is a plan view of the pressurizing chamber forming member viewed from the vibration direction. Fig. 3 is a view showing a slit-processed piezoelectric element. Figs. 4 (a) and 4 (b) are configuration examples of electrodes of the piezoelectric element. Diagram,
5 and 6 are views showing a head section of a conventional ink jet recording apparatus. 1 ... substrate, 2 ... piezoelectric element, 3 ... slit, 4 ...
Projection of piezoelectric element, 5 ... Pressure chamber, 6 ... Nozzle, 7 ...
Ink supply unit, 8: diaphragm, 9: pressure chamber forming member,
10 …… Nozzle plate.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Osamu Naruse 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Shuzo Matsumoto 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Tomoaki Nakano 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (58) Field surveyed (Int.Cl. ⁶ , DB name) B41J 2/045 B41J 2/055 B41J 2/16

Claims (1)

(57) [Claims] 1. A piezoelectric element is laminated on a substrate, a plurality of parallel slits are formed in the piezoelectric element, and a plurality of pressurizing chambers are formed corresponding to the protrusions of each piezoelectric element between the slits. One of the pressure chambers is connected to a nozzle, and the other is connected to an ink supply unit. The piezoelectric element applies an electric field in a direction perpendicular to a longitudinal direction of the slit and an array direction, so that a thickness displacement is performed in the same direction as the electric field. In an ink jet recording apparatus that ejects ink from nozzles, the piezoelectric element is divided into a plurality of blocks in the longitudinal direction of the slit, and the pressure chamber and the ink supply unit in the pressure chamber forming member also correspond thereto.
An ink jet recording apparatus characterized by ejecting ink in the pressure chamber forming member from a nozzle.