JPS58197058A - Ink jet head - Google Patents

Abstract

PURPOSE:To obtain an ink jet head capable of preventing the staying of air bubbles in a manifold, the lowering of vibrating efficiency, and disorder of print letters by setting an ink supply manifold of a nearly circular cross section and an ink jet nozzle in such a way as to deviate the nozzle port toward the vertical direction. CONSTITUTION:An ink jet head 5, in which an ink supply manifold 1 of a nearly circular cross section and an ink jet nozzle 2 of a nearly circular cross section are provided, the portion near the nozzle 2 at least of the ink supply manifold 1 to supply ink to the nozzle port 3 is shaped into a cylindrical form, and the ink supply manifold 1 and the nozzle port 3 of the ink jet nozzle 2 are deviated toward the vertical direction but not concentric, is used. By this, air bubbles can be easily discharged and stable printing can be made.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an inkjet head that has a simple structure and can easily remove air bubbles mixed in ink.

In an inkjet recording device, printing is performed by applying ultrasonic vibrations to the ink and ejecting ink droplets from the ink jet nozzle, and making the droplets fly to the recording medium. If the jetting does not stop instantaneously, it will stain the deflection electrodes and inks in front of the nozzle, and if the area around the nozzle hole gets dirty with ink, the jetting direction will change. Therefore, when the electromagnetic valve closes when jetting is turned off, the liquid chamber of the inkjet head is set to instantaneously become negative pressure.

For this reason, air is drawn from the nozzle hole when the injection is turned off, and if the bubbles are not ejected instantly when the injection is turned off, the air bubbles remaining in the liquid chamber act as a damper, reducing the vibration efficiency and causing the print. This will cause disturbances in the handwritten characters.

Figure 1 shows an example of the structure of a conventional inkjet head, where ] is an ink supply manifold, 2 is a nozzle, and 3 is a nozzle.
4 is a nozzle body, 5 is an inkjet head body, 6 is a vibrator, and 7 is a diaphragm.

In the inkjet head, the ink supply manifold 1 and the injection hole 3 of the nozzle 2 are coaxial, so if air bubbles are formed in the ink jet manifold, the air bubbles are not necessarily ejected when the injection is turned off, and it is difficult to take pictures. This may result in a decrease in dynamic efficiency.

The present invention has been made to eliminate these drawbacks.

FIG. 2 is a sectional view of an embodiment of the innocent head according to the present invention, and all the reference numerals are the same as those described in FIG. 1.

A feature of the present invention is that at least a portion of the ink supply manifold 1 near the nozzle 2 for supplying ink to the nozzle holes 3 is cylindrical, and the positional relationship between the ink supply manifold 1 and the nozzle holes 3 is not concentric. , 7Cr is offset in the vertical direction.

The best offset amount is when the upper edge of the ink supply manifold 1 and the upper edge of the nozzle hole 3 match, and Figure 3 shows the ink supply when the nozzle hole 3 is viewed from the front. This shows the eccentricity with respect to the manifold l.

If the deviation and L-meter are below the above, a step will appear between the upper edges of the rain, and air bubbles will likely remain.
Although the ease of removing air bubbles does not change much, the deformed state of the nozzle hole may affect the particle formation performance.

As mentioned above, the present invention has an extremely simple structure that allows air bubbles to be easily discharged and provides a highly reliable and stable inkjet nozzle, which is extremely effective in practice.

[Brief explanation of drawings]

Figure 1 shows the structure of a conventional ink/etch head.
FIG. 2 is an embodiment diagram for explaining the structure of an inkjet nozzle according to the invention, and FIG. 3 is an embodiment diagram showing the eccentricity of the nozzle hole and the ink supply manifold. 1: supply manifold, 2: nozzle, 3: nozzle hole, 4: nozzle body, 5: quick jet head, 6: vibrator, 7: diaphragm.

Claims (1)

[Claims] C1+ has an ink supply manifold having a substantially circular cross section, and an ink jet nozzle having a substantially circular cross section;
An inkjet head characterized in that the ink supply manifold and the nozzle hole of the ink jet nozzle are vertically eccentric. (2) The inkjet printer according to claim (1), wherein the upper edge of the nozzle hole of the ink jet nozzle and the upper edge of the ink supply manifold are substantially aligned.
To”no do.