JPH03284950A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To obtain an ink jet recording device capable of preventing mutual interference of adjacent nozzles by changing the substantial Young's modulus at a clearance part other than a part where a piezoelectric element of an oscillating plate is junctioned to a separation wall. CONSTITUTION:1 is a separation wall, 2 is a top plate, 3 is a pressure chamber, 4 is an oscillation plate, 5 is an electrode, 6 is a piezoelectric element and (a) is a clearance part. The oscillation plate 4 is notched and a recording liquid is discharged from a nozzle which communicates with the pressure chamber 3 by the inward displacement of the pressure chamber 3 following the application of a voltage to a laminated piezoelectric ceramic. A notch provided on the oscillation plate 4 is provided at the clearance part (a) between the piezoelectric element 6 and the partition wall 1. Mutual interference between adjacent nozzles does not occur, even if the part other than the clearance part (a) is composed of a plate of different thickness and different Young's modulus by making the Young's modulus at the clearance part (a) with a plate thickness a Young's modulus at which no mutual interference occurs using an unnotched oscillation plate 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inkjet recording device, and is applied to various recording devices, for example.

k-button technical rights As a description of the prior art related to the present invention, Japanese Patent Application Laid-Open No. 6
There is a publication No. 0-90770. This conventional example will be explained based on FIG. 7. In the figure, 11 is a partition wall, 12 is an upper plate, and 13
is a pressurized chamber, and 14 is a diaphragm.

15 is an electrode, 16 is a piezoelectric body, 17 is a groove, 18 is a rigid member, 19 is a convex portion, C is the width of the convex portion 19 (piezo width), and d is the width of the groove 17 (groove width).

With the configuration shown in FIG. 7, that is, due to the change in volume of the pressurizing chamber 13 due to the deformation of the piezoelectric body 16 via the diaphragm 14,
In a method of ejecting recording liquid from an ejection port communicating with the pressurizing chamber, the thinner the diaphragm 14 and the smaller its Young's modulus, the smaller the mutual interference with adjacent nozzles. but,
The thicker the diaphragm and the greater the Young's modulus, the more the following disadvantages occur.

1) Liquid ejection efficiency when the convex part (■) is driven alone.

The liquid ejection efficiency of the protrusion (■) changes when the protrusions (■) to (■) are simultaneously driven.

(2) When the convex parts (2) and (2) are driven without driving the convex part (2), the recording liquid drips or spills from the convex part (2) when the driving pulse is turned off.

The above drawbacks i) and ii) are both due to the upper plate 2 being deformed upward via the diaphragm 14, and the rigid member 18
Even if the Young's modulus is increased, as the number of nozzles increases, the drawbacks i) and ii) become unavoidable.

On the other hand, 6 with piezo @ C of 100 μm and groove @ 70 μm
In order to achieve a high degree of integration of 1/2 or higher and to eliminate the above-mentioned mutual interference, the thickness of the diaphragm 14 must be 20 μm or less, and its Young's modulus must be several hundred or less (resin or rubber material).
4 has disadvantages such as poor handling and assembly, and at the same time, a bonding method that requires high-temperature treatment cannot be used.

■--Defeat The present invention was made in view of the above-mentioned circumstances,
The purpose of this invention is to provide an inkjet recording device in which mutual interference between adjacent nozzles is prevented by changing the substantial ring rate of the clearance portion other than the joint portion between the piezoelectric material of the diaphragm and the partition wall. It is something.

In order to achieve the above object, the present invention includes a piezoelectric body in which a plurality of grooves are formed, and a pressurizing chamber that is arranged opposite to the piezoelectric body divided by the grooves with a diaphragm interposed therebetween. In an inkjet recording apparatus, the piezoelectric body of the diaphragm and the upper plate are configured to eject recording liquid from an ejection port communicating with the pressurizing chamber due to a change in volume of the pressurizing chamber due to deformation of the piezoelectric body. The elastic modulus of the elastic body near the joint part is made substantially larger than the elastic modulus of the elastic body in the non-joint part. Hereinafter, the present invention will be explained based on examples.

FIG. 1 is a block diagram for explaining an embodiment of an inkjet recording apparatus according to the present invention.

1 is a partition wall, 2 is an upper plate, 3 is a pressurizing chamber, 4 is a diaphragm, 5 is an electrode, 6 is a piezoelectric body, 7 is a groove, and a is a clearance portion.

The diaphragm 4 has a notch, and recording liquid is ejected from a nozzle communicating with the pressurizing chamber 3 by displacement of the pressurizing chamber 3 inward as a voltage is applied to the laminated piezoelectric ceramic. The notch provided in the diaphragm 4 is provided in the clearance part a between the piezoelectric body 6 and the partition wall 1, and the plate thickness and Young's modulus of the clearance part a can be adjusted to the Young's modulus without mutual interference with the diaphragm 4 without a notch. It was found that the mutual interference does not change even if the parts other than the clearance part a are printed with other plate thicknesses or Young's modulus.

FIGS. 2 to 4 are diagrams showing other embodiments of the diaphragm provided with notches. Reference numbers in the figure are the same as in FIG. When using a resin with a Young's modulus of about 400 Kg/a++u'', the thickness of the clearance part should be 30μ or less, and almost no mutual interference will be observed.From the viewpoint of handling and ease of assembly, the thickness beyond the clearance should be 60μ. or more is desirable. Stainless steel or silicone (Young's modulus approximately 20,000 kg/l)
llm2) and glass (Young's modulus approximately 8000Kg/av+
2) can also be used as a diaphragm. In this case, the thickness of the clearance portion is 10 μm or less, and almost no mutual interference is observed.

In the case of resin, the diaphragm is formed by integral molding or laminating, while stainless steel, silicone, glass, etc. are formed by etching, lamination, or #! A notch is formed by mechanical processing or the like.

FIG. 5 shows an example in which rubber is used as a diaphragm.

Is the Young's modulus of rubber 10? [g/11m" or less, and even if the plate thickness is thick (about 100 μI11), the mutual interference is significantly improved, but there are problems with the bonding method. The rubber thin film 9 is covered with an M layer of stainless steel 8, etc. It was found that mutual interference was completely eliminated by removing the clearance section.

FIG. 6 shows an example in which the diaphragm does not have a notch. A is made of a material with a large Young's modulus such as stainless steel, silicon, or glass, and B is made of a resin or rubber material. It was found that t5 of interference was caused.

As is clear from the above explanation, according to the present invention, a recording head free from mutual interference can be achieved by changing the substantial ring rate of the clearance portion other than the joint portion between the piezoelectric material of the diaphragm and the partition wall. can. Further, if the Young's modulus of the clearance MS is inappropriate, it is necessary to increase the clearance in order to reduce mutual interference, and high integration can be achieved by changing the Young's modulus of the clearance portion from others.

[Brief explanation of drawings]

FIG. 1 is a block diagram for explaining one embodiment of an inkjet recording apparatus according to the present invention, FIGS. 2 to 4 are diagrams showing other embodiments of a diaphragm provided with a notch, and FIG. This figure shows an example in which rubber is used as the diaphragm, FIG. 6 shows an example in which the diaphragm does not have a notch, and FIG. 7 is a configuration diagram of a conventional head section. 1... Recessed wall, 2... Top plate, 3... Pressure chamber, 4...
・Vibration plate. 5... Electrode, 6... Piezoelectric body, 7... Groove, a...
Clearance department.

Claims (1)

[Claims] 1. Consisting of a piezoelectric body in which a plurality of grooves are formed, and an upper plate having a pressurizing chamber arranged opposite to the piezoelectric body separated by the grooves via a vibration plate, the piezoelectric body is pressurized by deformation of the piezoelectric body. In an inkjet recording device in which recording liquid is ejected from an ejection port communicating with the pressurizing chamber due to a change in the volume of the chamber, the elastic modulus of the elastic body near the joint between the piezoelectric body of the diaphragm and the upper plate is adjusted to non-bond. An inkjet recording device characterized in that the elastic modulus of the elastic body is substantially larger than that of the elastic body of the inkjet recording device.