JP2981499B2 - Inkjet head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art For example, JP-A-63-247051 discloses a shear mode type ink jet head. As shown in FIG. 4, a plurality of ink flow paths 4 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, an 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 overlapped on the substrate 41 so as to cover the ink flow path 42, and nozzles 47 to 47 are formed on the end surface thereof. A plate 48 is attached, and by applying a voltage to the electrodes 43, the partition walls are deformed in a shear mode to discharge ink from the nozzles 47.

[0003]

The above-mentioned conventional device has a problem in a method of connecting an electrode and a 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 that the interval between the lead wires must be narrowed. The lead wire and the drive circuit are generally connected by wire bonding. However, as the distance between the lead wires becomes narrower, it becomes difficult to connect the wire while maintaining the mechanical strength of the wire.

[0005] In order to obtain high quality recording with an ink jet head, 300 dpi (about 85 µm pitch) or more is required. It is sufficiently possible to mechanically cut a substrate made of a piezoelectric material such as PZT using a dicing saw or the like to form an ink flow path at an 85 μm pitch (for example, a groove width of 45 μm and a wall width of 40 μm), When making electrical connection with a drive circuit by bonding, it is very difficult to achieve an 85 μm pitch 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 for the above-described conventional apparatus to sufficiently narrow the nozzle pitch in order to obtain high-quality recording.

An object of the present invention is to provide an ink jet head having a configuration in which electrodes 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, there is provided a head substrate having a plurality of ink flow paths separated by a pressure partition made of a piezoelectric material, and a plurality of ink flow paths provided on a wall surface of each ink flow path of the head substrate. In an inkjet head having an electrode and electrical wirings respectively drawn out from each of the electrodes, and applying a voltage to the electrode to deform a wall surface of the ink flow path to discharge ink from a nozzle, The object is attained by drawing out the electrical wiring of the electrodes of the ink flow path in different directions.

[0009]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the structure of a flow path substrate of an ink jet head according to the present invention. In the figure, 11 is PZT
A channel substrate made of a piezoelectric material such as a plurality of ink channels separated from each other by a pressure partition made of a piezoelectric material;
Reference numeral 13 denotes an electrode provided on the wall surface of the ink flow path 12, and reference numeral 14 denotes a drive circuit (not shown) for selectively applying a voltage to the electrode 13.
And a lead wire for electrically connecting the electrode 13 to the electrode 13. The lead wire is drawn 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 denotes a nozzle formed on the bottom surface of the ink flow path 12.

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

The completed flow path substrate 11 has
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, thereby forming an ink jet head. Complete.

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

In the above embodiment, the nozzles 15 are formed on the bottom surface of the ink flow path 12. However, the present invention is not limited to this. As shown in FIG.
May be provided. In this case, it is desirable to use a 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 increase the interval between the lead wires connecting the electrodes provided in a plurality of ink flow paths and the drive circuit without increasing the dot pitch. It is possible to realize an ink jet head which can be easily connected to the ink jet head and can perform high quality recording.

[Brief description of the 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 ink jet head according to the present invention.

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Flow path board 12 Ink flow path 13 Electrode 14 Lead wire 15 Nozzle

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-363250 (JP, A) JP-A-4-148934 (JP, A) JP-A-4-107150 (JP, A) JP-A-4-107 169237 (JP, A) JP-A-3-272855 (JP, A) JP-A-5-229116 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 2/045 B41J 2 / 055

Claims (1)

(57) [Claims] 1. A head substrate in which a plurality of ink channels separated by a pressure partition made of a piezoelectric material are formed, electrodes provided on a wall surface of each ink channel of the head substrate, and a withdrawn electrical wiring, in the ink jet head allowed to eject ink from the nozzles by deforming the wall of the ink passage by applying a voltage to the electrode, the ink flow adjacent separating the pressure bulkhead An ink jet head characterized in that the electrical wiring of the electrodes of the path is drawn in different directions.