JPH10119266A - Ink jet recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a wire bonding process by a method wherein an electroconductive route and a via hole are formed to a cover plate, and a signal electrode formed inside a partition wall between kerfs of a piezoelectric ceramics board is electrically connected to an electroconductive route via a via hole. SOLUTION: An electric circuit 19 generating driving voltage and an electroconductive pattern for application of driving volatage 14 at a position corresponding to each channel are formed on a printed substrate 20 wherein a cover component and a printed-wiring board are integrally formed. Further, a via hole 13 introducing the electroconductive pattern 14 to a rear face is formed. Then, the printed substrate 20 is connected to an actuator component 1 so that the via hole 13 is electrically connected to each input terminal formed on a surface near a rear end part of the actuator component 1 with a conductive adhesive or the like. Thereby, a wire bonding process can be eliminated, and the number of pieces of parts can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a plurality of parallel channels separated by a partition made of piezoelectric ceramics, wherein the plurality of channels are arranged in accordance with the presence or absence of a drive voltage to a signal electrode formed on the inner wall of the channel. Deform the partition,
The present invention relates to an ink jet recording head that selectively causes ink filled in the channel to protrude from an ink discharge port connected to the channel due to the deformation, and particularly relates to a means for applying a drive voltage to the signal electrode. It has features.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 63-2527
As disclosed in Japanese Patent Publication No. 50, an ink jet recording apparatus using a shear mode deformation of a piezoelectric element as an ink ejection principle has been considered. This structure is, as shown in FIG. 2, an actuator member 1 made of a piezoelectric ceramic plate.
, A cover plate 3, a nozzle plate 2, and a printed wiring board 6. The actuator member 1 has a plurality of cut grooves 9 formed on the surface of the piezoelectric ceramic plate such that one end is opened on the side surface of the piezoelectric ceramic plate by diamond blade or the like, and the other end is formed in parallel with each other. Have been. In addition, the kerf 9
The partition 10 between them is subjected to a polarization treatment in the groove depth direction.

The incisions 9 have the same depth and are parallel to each other, and the depth of the incisions 9 is gradually reduced toward the rear end face 11 of the actuator member 1 as shown in FIG. A shallow channel region is formed near the end face 11. The signal electrode 4 is formed on the upper half of the surface of the partition 10 on both sides of each cut groove 9 by sputtering, vapor deposition, or the like. Similarly, in the shallow region of the kerf 9, the signal electrode 4 is formed on the side and bottom surfaces by sputtering, vapor deposition, or the like. Thereby, the signal electrodes 4 formed on both side surfaces of the cut groove 9 are electrically connected by the conductive layer formed simultaneously with the signal electrode 4 formed on the bottom surface of the shallow region of the cut groove 9. The conductive layer is also continuously formed on the surface 17 near the rear end face 11 of the actuator member 1 to form a drive signal input terminal for the signal electrode 4 in each kerf.

[0004] The cover plate 3 is formed of an insulating material such as a ceramic material or a resin material. The cover plate 3 has an ink supply port 8 and a manifold 7 formed by grinding or cutting. Then, the processing-side surface of the channel 9 of the actuator member 1 and the processing-side surface of the manifold 7 of the cover plate 3 are adhered with an epoxy-based adhesive 12. In this way, the upper surface of the kerf 9 is covered to form a plurality of channels having the same interval in the lateral direction. The channels (cut grooves 9) have an elongated shape with a rectangular cross section, and all the channels are filled with ink from the ink supply ports 8.

Further, as shown in FIG. 3, the nozzle plate 2 is arranged so that the ink discharge ports 5 are located at the positions corresponding to the positions of the respective channels (cut grooves 9) on the end surfaces of the actuator member 1 and the cover plate 3. Is glued. The nozzle plate 2 is formed of a plastic such as polyimide, polyetherimide, polyetherketone, polyethersulfone, and polycarbonate.

A printed wiring board 6 is adhered to the back surface of the actuator member 1 with an epoxy-based adhesive or the like. The printed wiring board 6 is formed with an electric circuit section 19 for generating a drive voltage and a conductive pattern for applying the drive voltage at a position corresponding to each channel. Each conductive pattern and each input terminal formed on the surface 17 near the rear end face 11 of the actuator member 1 are connected by a bonding wire 16.

[0007]

In the above-described conventional configuration, the same number of bonding wires as the ink discharge channels formed in the piezoelectric ceramic are required. This is a process that increases the number of steps and is a problem in reducing the head cost. An object of the present invention is to provide a cheaper and simpler ink jet recording head by eliminating a wire bonding step with poor workability and reducing the number of parts.

[0008]

According to the present invention, a plurality of cut grooves are formed on the surface of a piezoelectric ceramic plate so that one end is open on the side surface of the piezoelectric ceramic plate and the other end is formed in parallel with each other. A nozzle plate formed and formed with a plurality of ink ejection holes is joined to a side surface of the piezoelectric ceramic plate so that each ink ejection hole faces one of the cut grooves. The cover plate is joined so as to cover each of the kerfs so that the kerfs are sealed, and depending on the presence or absence of a drive voltage to the signal electrode formed inside the partition between the kerfs, the partition is formed. In the ink jet recording head, which is deformed and selectively protrudes the ink filled in the kerf with the deformation from the ink discharge port communicating with the kerf, A conductive path for applying a drive voltage to the signal electrode is formed on the cover plate, and the conductive path is formed via a via hole formed in the cover plate by joining the cover plate to the piezoelectric ceramic plate. It is characterized by being electrically connected to each signal electrode, does not require a wire bonding step, and can be expected to be reduced in size by integrating the cover member and the printed wiring board.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention described in claims 1 and 2 of the present invention will be described below with reference to FIG. It should be noted that components substantially the same as those of the conventional example shown in FIGS. 2 and 3 are denoted by the same reference numerals.

A feature of the embodiment of the present invention is that, as shown in FIG. 1, a conventional cover member 3 and a printed wiring board 6 are made of glass ceramics used in HIC technology. The point is that the printed circuit board 20 integrally formed as described above is used as a cover member. That is, the printed circuit board 20 is formed with an electric circuit section 19 for generating a driving voltage and a conductive pattern 14 for applying the driving voltage at a position corresponding to each channel. Is formed by HIC technology. In addition, on the back surface of the rear end portion of the printed circuit board 20, irregularities 1 for heat dissipation are provided.
8 are integrally formed. The main purpose of the heat radiation unevenness 18 is to radiate heat from an electric circuit section 19 such as an IC mounted on the opposite side.

The printed circuit board 20 has a via hole 13
Are connected to the actuator member 1 such that the input terminals formed on the surface near the rear end of the actuator member 1 are electrically connected by a conductive adhesive or the like.

In this manner, the conventional shear mode type ink jet recording head can be manufactured at a low cost without requiring a process such as wire bonding as an electric connection means for giving a signal for ink ejection as in the prior art. Can be made.

[0013]

According to the ink jet recording head of the present invention, there is no need for a wire bonding apparatus required for conduction between the signal electrode formed on the inner wall of the ink channel and the printed circuit board pad, and the number of parts is small and the man-hour is small. Will also be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an ink jet recording head according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a conventional shear mode type ink jet recording head.

FIG. 3 is a cross-sectional view in the longitudinal direction of a channel of the conventional ink jet recording head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Actuator member 2 Nozzle plate 3 Cover plate 4 Signal electrode 5 Nozzle 7 Manifold 8 Ink supply port 9 Cut groove (channel) 10 Actuator side wall 11 Actuator member rear end face 12 Epoxy adhesive 13 Via hole 14 Conductor pattern 18 Heat radiation unevenness 19 Electricity Circuit 20 Printed circuit board

Claims (2)

[Claims] 1. A plurality of cut grooves formed on a surface of a piezoelectric ceramic plate, one end of which is open on a side surface of the piezoelectric ceramic plate, and the other end of which is gradually reduced in parallel, and
A nozzle plate having a plurality of ink ejection holes is joined to a side surface of the piezoelectric ceramic plate such that each ink ejection hole faces one of the cut grooves, and a cover plate is provided on the surface of the piezoelectric ceramic plate. Joining so as to cover each of the kerfs, making the kerfs hermetically sealed, depending on the presence or absence of a drive voltage to a signal electrode formed inside the barrier between the kerfs, deforming the barrier, An ink jet recording head for selectively projecting ink filled in the kerf from the ink discharge port communicating with the kerf along with the deformation, wherein a drive voltage to the signal electrode is applied to the cover plate. A conductive path for applying voltage is formed, and the conductive path is formed on the cover plate by joining the cover plate to the piezoelectric ceramic plate. An ink jet recording head is characterized in that respectively electrically connected to the signal electrode via holes. 2. The cover plate according to claim 1, wherein an electric circuit for generating the drive voltage is provided on the cover plate, and irregularities for heat radiation are integrally formed. Ink jet recording head.