JPH04148936A - Ink jet recording head - Google Patents

Abstract

PURPOSE:To provide a certain ink chamber generating no stagnation of air bubbles by providing a plurality of pressure chambers to one surface of a head substrate in a depressed state and providing the communication passages to a nozzle opened to the opposite surface of the substrate from the end parts of the pressure chambers and providing the communication passages to an ink chamber provided to the opposite surface of the substrate in a depressed state from the other ends of the pressure chambers. CONSTITUTION:Pressure chambers 2 are arranged to one surface of a head substrate 1 and ends 2a of the pressure chambers 2 communicate with an ink emitting nozzle 8. The other ends 2b of the respective pressure chambers 2 communicates with the ink chamber 4 provided to the surface opposite to the surface having the pressure chambers 2 formed thereto of the substrate through throttled parts 3. By setting the ink chamber 4 communicating with the pressure chambers 2 in an annular shape, even when air bubbles enter the ink chamber 4, they are not stagnated because the ink from an ink supply pipe 9 flows and circulates within the ink chamber 4 by the suction from the nozzle and can be easily discharged through the pressure chambers.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inkjet recording head used in an inkjet printer.

[Conventional technology]

In order to meet the demands for high print quality and low cost for inkjet printers, it is necessary to increase the nozzle density, and a simpler structure is required. As seen in Japanese Patent No. 172, an inkjet recording head has a plurality of pressure chambers and a U-shaped ink chamber arranged around the common substrate, and ejects ink droplets from nozzles opened on the opposite side. Proposed.

However, with such a recording head, it is difficult to form a communication path between the pressure chamber and the ink chamber, and even if it were possible to form it, it would be difficult to measure its dimensions, making it difficult to manage, resulting in variations in the characteristics of each nozzle. All we could do was stabilize the characteristics and improve the quality of printing.

In addition, air bubbles remain in the ink chamber and tJI cannot be discharged.

Furthermore, because the flow channels are arranged in a planar manner, the head substrate becomes large, and when installed in an inkjet printer, the part facing the paper surface is wide, causing paper abrasions, print stains, and other problems.

[Problem to be solved by the invention]

The present invention has been made in view of these problems, and its purpose is to propose a new inkjet recording head with high print quality, high reliability, and simple structure.

[Means to solve the problem]

That is, the present invention is directed to solving such problems. As a recording head, a plurality of pressure chambers are recessed on one surface of a head substrate, and the ends of the pressure chambers are opened to the opposite surface of the substrate. In addition to providing a communication path to the nozzle, a communication path is provided from the other end of each pressure chamber to an ink chamber recessed on the opposite surface of the substrate, and a communication path from each pressure chamber to the ink chamber is provided. The communication path has a constriction part, and each of the proof parts and the ink discharge nozzle are oriented perpendicular to the plane in which the pressure chamber is formed. Further, ink chambers are arranged in a ring shape 17, and ink is supplied to a part of the chambers.

Further, a plurality of pressure chambers formed on one surface of the head substrate 17 and an ink chamber formed on the opposite surface are arranged so as to overlap with each other.

〔Example〕

Therefore, the illustrated embodiment will be explained below.

FIG. 1 is a 3'T1 plane view of an inkjet recording head according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along EE in FIG. 1. In FIG. 1, the cover plate 5, nozzle brake 1-6, and drive element 7 shown in FIG. 2 are omitted.

In the figure, pressure chambers 2 are arranged on one surface of the head substrate, and one end 2a of each pressure chamber 2 communicates with an ink discharge nozzle 8, as shown in FIG. The other end 2b of each pressure chamber 2 communicates with an ink chamber 4 provided on a surface opposite to the surface on which each pressure chamber 2 is formed via a constriction portion 3.

In FIG. 2, 5 is a cover plate that covers the pressure chamber 2, 7 is a drive element for generating pressure, and 6 is a nozzle plate that forms the ink chamber 4 and also has a nozzle 8.

The ink chamber 4 is provided in an annular shape as shown by the broken line in FIG. 1, and the ink chamber 4 is arranged so as to overlap the pressure chamber 2. Ink is supplied from the ink cartridge through the ink supply vibrator 9. The ink chamber 4 is formed by a smooth line with no corners.

A series of flow paths such as the pressure chamber 2, ink chamber 4, and constriction section 3 can be formed by injection molding, etching, etc., but the precision is a few micrometers due to the fine openings. The nozzle 8 and the constriction part 3 that require the following can be made with a laser beam that irradiates the pressure chamber 2 from the pli direction, or can be made with particularly high precision using a fine drill.

FIG. 3 shows another embodiment of the ink jet recording head according to the present invention, in which an ink chamber 4 is formed by a plate 1 and nozzles 8 are formed directly on the head substrate 1.

According to the structure of the above embodiment, it is possible to easily realize a plurality of ink ejection nozzles 8 and communication passages, particularly the constriction portion 3, which require fineness and high precision. (7) The nozzle 8 and the aperture part 3 are both transparent, so they can be easily measured.
Therefore, J-method inspection and its management can be performed.

By setting the ink chamber 4 communicating with each pressure chamber 2 in an annular shape, even if air bubbles enter, the ink from the ink supply vibrator 9 circulates in the ink chamber 4 by suction from the nozzle side and does not stagnate. , bubbles can easily come out through the pressure chamber. Furthermore, when operating as an inkjet printer, for example, the nozzles that communicate with the upper pressure chamber in Figure 1 may eject all nozzles, and the nozzles that communicate with the lower pressure chamber may eject only a few nozzles. Ink can be almost evenly supplied from the valve 9 to each pressure chamber, and there is no difference in ink supply conditions to each nozzle, and uniform ejection characteristics can be obtained from each nozzle.

By arranging the pressure chamber 2 and ink chamber 4 overlapping each other, the width of the head can be reduced, and when installed in an inkjet printer, important advantages such as prevention of paper abrasion and expansion of the printing area on the paper surface can be achieved. I can eat a cow.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to apply equal ink droplet ejection conditions to all nozzles with a simple structure, and to provide a reliable ink chamber in which air bubbles do not remain. It can be configured as an inkjet recording head.

Furthermore, it is possible to construct a head with reduced width usage.

4. Simple explanation of the drawings Fig. 1 shows a head according to an embodiment of the present invention, Fig. 2 is a sectional view taken along line E-E of the same, and Fig. 3 shows a head according to an embodiment of the present invention. It is a figure showing one example of this.

・Head board・Pressure chamber・Aperture part・Ink chamber nozzle blurring “”

Claims (4)

[Claims] (1) A plurality of pressure chambers are recessed on one surface of the head substrate, and a communication path is provided from the end of each pressure chamber to a nozzle opening on the opposite surface of the substrate, and the other end of each pressure chamber is provided. An inkjet recording head characterized in that a communication path is provided from the section to an ink chamber recessed on the opposite surface of the substrate. (2) The communication path from each pressure chamber to the ink chamber has a constriction part, and each constriction part and the ink discharge nozzle are both perpendicular to the plane in which the pressure chamber is formed. The inkjet recording head according to claim 1. (3) The inkjet recording head according to claim 1, wherein the ink chambers are arranged in a ring shape, and ink is supplied to a part of the ink chambers. (4) The inkjet recording head according to claim 1, wherein the plurality of pressure chambers formed on one surface of the head substrate and the ink chambers formed on the opposite surface are arranged so as to overlap with each other.