JPH07137251A - Ink jet head - Google Patents

Abstract

PURPOSE:To provide an ink jet head which permits easy connection of lead wires from electrodes corresponding to plural nozzles respectively with a driving circuit and recording with high quality by leading out the lead wires in an opposite direction to the adjacent lead wire. CONSTITUTION:Plural ink flow passages 12 separated from each other by a pressure partition wall is formed in a substrate 11 consisting of piezoelectric material, and respective electrodes 13 are formed at the wall surfaces of the respective ink flow passages 12 to lead out the respective lead wires 14 from the respective electrodes 13 so that the adjacent lead wire 14 may be in an opposite direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shear mode type ink jet head.

[0002]

2. Description of the Related Art For example, Japanese Patent Laid-Open No. 63-247051 discloses a shear mode type ink jet head. This is because, as shown in FIG. 4, a plurality of ink flow paths 4 are separated from each other by partition walls made of a piezoelectric material by cutting or the like on a substrate 41 made of a piezoelectric material such as PZT.
2 to 42, the electrode 43 is formed on the wall surface of the ink flow path 42, and lead wires 44 to 44 for connecting the electrode 43 to a drive circuit (not shown) for applying a voltage to the electrode 43.
Are drawn out from the respective ink flow paths 42 in the same direction. Further, a cover plate 46 provided with an ink supply port 45 for supplying ink to the ink flow path 42 is superposed on the substrate 41 so as to cover the ink flow path 42, and nozzles 47 to 47 are formed on the end faces thereof. A plate 48 is attached, and by applying a voltage to the electrode 43, the partition wall is deformed in the shear mode and ink is ejected from the nozzle 47.

[0003]

The above-mentioned conventional devices have a problem in the method of connecting the electrodes and the drive circuit.

In order to obtain high quality recording with an ink jet head, it is necessary to narrow the nozzle pitch. In the ink jet head as described above, the nozzle pitch is determined according to the interval between the lead wires connecting the drive circuit and each electrode, so the interval between the lead wires must be narrowed. Generally, the lead wire and the drive circuit are connected by wire bonding. However, it becomes difficult to connect the lead wire while maintaining the mechanical strength of the wire as the space between the lead wires is narrowed.

In order to obtain high quality recording with the ink jet head, 300 dpi (about 85 μm pitch) or more is required. Mechanically cutting a substrate made of a piezoelectric material such as PZT with a dicing saw or the like to form an ink flow path is sufficiently possible with a pitch of about 85 μm (for example, a groove width of 45 μm and a wall width of 40 μm). When making an electrical connection with a drive circuit by bonding, it is very difficult to achieve a pitch of 85 μm while maintaining the mechanical strength of the wire. The current technology has a limit of about 120 μm pitch.

As described above, it is difficult to sufficiently narrow the nozzle pitch in order to obtain high quality recording in the above-mentioned conventional one.

An object of the present invention is to provide an ink jet head having a structure in which an electrode of each ink flow path and a drive circuit can be easily connected even if the nozzle pitch is narrow.

[0008]

According to the present invention, a head substrate having a plurality of ink channels separated by pressure barriers made of a piezoelectric material and a wall surface of each ink channel of the head substrate are provided. An ink jet head having electrodes and electric wirings drawn out from the respective electrodes, and applying a voltage to the electrodes to deform the wall surface of the ink flow path to eject ink from the nozzles is adjacent to each other. The above problem is solved by drawing out the electrical wiring of the electrodes of the ink flow path in mutually different directions.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of the flow path substrate of the ink jet head according to the present invention. In the figure, 11 is PZT
A flow path substrate made of a piezoelectric material such as, a plurality of ink flow paths 12 separated from each other by pressure partition walls made of a piezoelectric material,
Reference numeral 13 is an electrode provided on the wall surface of the ink flow path 12, and 14 is a drive circuit (not shown) for selectively applying a voltage to the electrode 13.
A lead wire for electrically connecting the electrode 13 and the electrode 13 is drawn out in the longitudinal direction of the ink flow path 12 so as to be opposite to the lead wire 14 from the adjacent ink flow path 12. Reference numeral 15 is a nozzle formed on the bottom surface of the ink flow path 12.

First, the flow path substrate 11 having such a structure is
The flow channel substrate 11 is mechanically cut with a dicing saw or the like to form the ink flow channel 12, and then a YAG laser, an excimer laser, or the like is irradiated to irradiate the nozzle 1 on the bottom surface of the ink flow channel 12.
5 is formed, and then, the electrode 13 and the lead wire 14 are formed by performing vacuum vapor deposition from an oblique direction using a metal material such as Al, Ni, and Cr.

On the flow path substrate 11 thus completed,
As shown in FIG. 2, a cover plate 22 having a common ink flow path 21 for supplying ink to the ink flow path 12 is overlapped and adhered so as to cover the ink flow path 12 to form an inkjet head. Complete.

Thereafter, the drive circuit (not shown) and the lead wire 14 are connected by wire bonding or the like. At this time, since the lead wires 14 are alternately pulled out in the opposite direction as described above, the interval between the lead wires 14 becomes wider (for example, if the nozzle density is 300 dpi, the lead wires 14 are
Is about 170 μm), and connection with a drive circuit by wire bonding can be easily performed.

Although the nozzle 15 is formed on the bottom surface of the ink flow path 12 in the above embodiment, the present invention is not limited to this, and the nozzles 32 to 32 are provided on the cover plate 31 as shown in FIG.
May be provided. In this case, it is desirable to use photosensitive glass or the like as the cover plate material and process the nozzle by etching.

[0015]

According to the present invention, it is possible to widen the intervals between the lead wires connecting the electrodes provided in a plurality of ink flow paths and the drive circuit without widening the dot pitch. It is possible to realize an ink jet head that can be easily connected to and that enables high quality recording.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration example of a flow path substrate of an inkjet head according to the present invention.

FIG. 2 is an explanatory diagram showing a configuration example of an inkjet head according to the present invention.

FIG. 3 is an explanatory view showing another configuration example of the inkjet head according to the present invention.

FIG. 4 is an explanatory diagram showing a configuration of a conventional inkjet head.

[Explanation of symbols]

 11 flow path substrate 12 ink flow path 13 electrode 14 lead wire 15 nozzle

Claims (1)

[Claims] 1. A head substrate in which a plurality of ink channels separated by pressure barriers made of a piezoelectric material are formed, electrodes provided on the wall surfaces of the ink channels of the head substrate, and electrodes from the respective electrodes. In an inkjet head that has a drawn electrical wiring and discharges ink from a nozzle by applying a voltage to the electrode to deform the wall surface of the ink flow path, the electrical The inkjet head is characterized in that the wiring is drawn out in different directions.