JPS60232967A - Ink jet head - Google Patents

Abstract

PURPOSE:To make printing by a small amount of applied energy possible and further to separately form ink pressure chambers and ink supply passages on a thin sheet and form plural nozzles in a high density, by a method wherein the generated pressure caused by the bend deformation of piezo vibrator is effectively used only for injection of ink drop. CONSTITUTION:Two ink pressure chambers 102 are formed almost parallel to each other on a base plate 107 and piezo vibrators 105 are adherred onto an upper plate 106 so as to be located just over the ink pressure chambers 102. Two ink supply passages 111 are formed on a supply plate 110 and connected to the ink pressure chambers 102 and a nozzle 101 with the combination hole 103 installed near the front edge of a bypass plate 109. The ink pressure chambers 102 are equipped with only one open port A and the nozzle 101 is provided, the nozzle port X of which faces the plate end. That is, by constructing respective plates 106-108 by parallel lamination, the ink pressure chambers 102 and the ink supply passages 111 are, in three dimensions, constructed and the pressure generated with the piezo vibrators 105 effectively acts only as pressurizing to the ink pressure chambers 102 to be used for welling out of ink.

Description

DETAILED DESCRIPTION OF THE INVENTION [Differential Field of Application] The present invention relates to a print head for an inkjet printer, and particularly to an inkjet head used for a printhead that forms characters or figures using a dot matrix.

[Prior art]

In recent years, with the spread of office automation, there has been an increasing demand for documents to be created in the office and printed on the spot.
In order to keep the room quiet, the printer is equipped with low noise and high printing quality. Furthermore, with the spread of personal computers, there is an increasing demand for outputting characters and figures on digital displays in color, and inkjet printers have been put into practical use as one of the printers that meet these demands.

This inkjet printer uses techniques such as photoetching to form the nozzle section, ink pressurizing chamber, and ink supply section, and the ink pressurizing chamber is formed by bending and deforming a piezo vibrator bonded to the outer wall of the ink pressurizing chamber. The capacity of the nozzle is changed to eject ink droplets from the tip of the nozzle.

Such an inkjet head is shown in FIGS. 1 and 2.

In this example, a nozzle plate 7 on which ink passages for the nozzle 1, ink pressurizing chamber 2, and ink supply section 3 are formed is layered on a pace plate 8 by photo-etching, and a diaphragm 6 is bonded onto the etched surface. A piezo vibrator 5 is adhered to the outer wall of a diaphragm 6 on an ink pressurizing chamber 2 provided on a nozzle plate 7 to form a nozzle section 4.

A typical busy inkjet head has a plurality of such nozzle sections 4 formed on a single nozzle plate 7, and drives a piezo vibrator 5 as necessary to form characters or figures on paper using dots. be.

However, depending on such a configuration, the piezo vibrator 5
The generated pressure is transmitted in both directions to the nozzle 1 and the ink supply section 3, and only about half of the applied pressure can be used to eject ink droplets, so the applied energy is used effectively. The drawback was that it was not possible.

[Purpose of the invention]

An object of the present invention is to provide an inkjet head that has nozzles that eject necessary ink droplets with less applied energy and that can mount a plurality of nozzles at high density on the same surface.

[Structure of the invention]

The inkjet head that detects pressure according to the present invention applies voltage to a piezoelectric vibrator installed on the outer wall of an ink pressurizing chamber, and by bending and deforming the piezoelectric vibrator, ink flows through the nozzle opening of a nozzle communicating with the ink pressurizing chamber. The first inkjet head is an on-demand type inkjet head that ejects droplets, and has one or more sets of an ink pressurizing chamber having only one opening and one or more nozzles connected to the opening and having a nozzle opening facing the end of the plate. a thin plate of
A second thin plate having an ink supply path communicating with an ink supply source is laminated in parallel, and one end of the ink supply path is connected with a connecting hole near the nozzle opening of the nozzle.

〔Example〕

Next, one embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a plan view showing the nozzle portion of the inkjet head according to the present invention, FIG. 4 is a cross-sectional view taken along the line ■--■ in FIG. 3, and FIG. 5 is a perspective view of the laminated state. The inkjet head of this embodiment includes an upper plate 106, a nozzle plate 107, a bypass 7' tray 109, a supply plate 110. Pace plate ios and upper plate 1
It is composed of a piezo vibrator 105 positioned on the outer wall of 06, and each plate is laminated and bonded in the order shown.

Two ink pressurizing chambers 102 are formed approximately in parallel on the pace plate 107 (first thin plate) by photoetching, and the piezo vibrator 105 is connected to the ink pressurizing chambers 102.
It is attached on the upper plate 106 so as to be located directly above the top plate 106. Two ink supply passages 111 are formed in the supply plate 110 (second thin plate), and a connection hole 103 provided near the front end of the bypass plate 109 connects the ink pressurizing chamber 102 and the nozzle 101. connected.

The ink pressurizing chamber 102 has only one open port A as shown in the figure.
A nozzle 101 is provided here, with a nozzle opening X facing the end of the plate. That is, each plate 106~
108 are stacked in parallel, the ink pressurizing chamber 102 and the ink supply path 111 are structured three-dimensionally, and the pressure generated in the piezo vibrator 105 is efficiently applied to the ink pressurizing chamber 102. It is a trap that only works on ink and is used to eject ink.

〔Effect of the invention〕

Since the inkjet head according to the present invention is as described above, the pressure generated by the bending deformation of the piezo vibrator is effectively used only for ejecting ink droplets.
Printing can be performed with less applied energy.Since the ink pressurizing chamber and the ink supply path are formed on separate thin plates, it has become possible to form a plurality of nozzles at high density.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the nozzle part of a conventional inkjet head, FIG. 2 is a sectional view of the conventional inkjet head taken along the line ■-■ in FIG. 1, and FIG. 3 is an inkjet head according to the present invention. FIG. 4 is a plan view showing the nozzle portion of one embodiment; FIG. 4 is a sectional view of the inkjet head according to the present invention taken along the line ■-■ in FIG. 3; FIG. It is. 101... Nozzle tip 102... Ink pressurizing chamber, 103... Connection hole 104... Nozzle part 105.
・Piezo vibrator 106 ・Upper plate 107・
... Nozzle plate [first thin plate] 108 ... Base plate) 109 ... Bypass plate 110 ...
Supply plate [second thin plate] 111... Ink supply path A... Opening port X... Nozzle port Applicant: NEC Corporation Figure 1 Figure 2 Figure 3 Figure 5

Claims (1)

[Claims] An on-demand type in which a voltage is applied to a piezo vibrator installed on the outer wall of an ink pressurizing chamber, and ink droplets are ejected from the nozzle opening of a nozzle communicating with the ink pressurizing chamber by bending and deforming the piezo vibrator. In the inkjet head, a first thin plate having one or more sets of an ink pressurizing chamber having only one open opening and one or more sets of nozzles connected to the opening and having a nozzle opening facing the end of the plate communicates with an ink supply source. An inkjet head characterized in that a second thin plate having an ink supply path is laminated in parallel, and one end of the ink supply path is connected by a connecting hole near the nozzle opening of the nozzle.