JPS60204353A - Liquid jet recording apparatus - Google Patents

Abstract

PURPOSE:To provide the titled apparatus capable of preventing the leakage of ink and enabled in miniaturization, having simple constitution such that a liquid jet means and a container for receiving an injected liquid are provided and an air passing means fine enough to prevent the natural outflow of the liquid in the container is provided to the lower part of said container. CONSTITUTION:In a liquid jet recording apparatus having a liquid jet means and a container for receiving the liquid injected from said liquid jet means, the fine tube 13 of an air passing means fine enough to prevent the natural outflow of the recording liquid ink 10 in an ink tank 7 being a container receiving said recording liquid ink 10 is provided to the lower part of said ink tank 7. An ink meniscus is formed in the fine tube 13 of the air passing means and the ink in a nozzle 8 is always held under atmospheric pressure or less and, when the ink 10 is reduced upon the emission of the ink 10 from an emitting orifice 11, the pressure in the tank 7 is reduced and the leakage of the ink from the ink emitting orifice 11 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a liquid jet recording device, and more particularly to a liquid jet recording device with an improved liquid supply mechanism.

[Prior art]

FIG. 1 is a perspective view showing an example of a conventional liquid jet recording device.

In the figure, a recording head 1 is fixed on a carriage 2 and ejects liquid (ink) while traveling in the direction of an arrow M. Further, the platen 3 rotates in the direction of arrow S1'1) to move the recording paper 4.

The recording head 1 is provided with an ejection port that ejects ink toward the recording paper 4 and a sub-tank that supplies ink to the ejection port, and the sub-tank is connected to a main tank 6 via a tube 5 that supplies ink. has been done.

In such a conventional device, ink is supplied to the sub-tank from the main tank 6 via the tube 5, but in order to keep the pressure inside the sub-tank below atmospheric pressure, the main tank 6 is placed below the recording head 1. It is located in This is because if the pressure inside the sub-tank is equal to or higher than atmospheric pressure, ink may leak from the ejection port even with the slightest impact, staining the recording paper 4 and the apparatus.

However, such a conventional configuration requires a main tank and a sub-tank, and the main tank must be provided below the sub-tank, making it difficult to downsize the device.

Furthermore, since the tube 5(2) moves with the movement of the print head 1, the ink pressure within the print head r1 fluctuates, which has a negative effect on the ink ejection characteristics. In order to eliminate this drawback, the main tank 6 may be fixed to the carriage 2, but since the main tank 6 needs to be placed below the sub-tank, it is not possible to downsize the device.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional drawbacks, and its object is to provide a liquid jet recording device that can prevent ink leakage with a simple external structure and can be downsized.

[Structure of the invention]

In order to achieve the above object, a liquid jet recording apparatus according to the present invention is characterized in that a liquid jet means and a container are integrated, and a sufficiently thin ventilation means is provided in the lower part of the container.

Here, the liquid ejecting means may be of any type as long as it ejects the liquid by energization, such as a nozzle using a piezoelectric element or a nozzle using thermal energy of a heating element.

The container is an ink tank that stores the liquid to be ejected, and incorporates the liquid ejecting means.

Further, a vent means is provided at the bottom or lower side of the container, and has a diameter so small that the liquid in the container does not naturally flow out.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 2 is a sectional view of a recording head in an embodiment of a liquid jet recording apparatus according to the present invention.

In the figure, an ink tank 7 includes a nozzle 8 and a cylindrical piezoelectric element 9 surrounding the nozzle 8. The ink 10 stored in the ink tank 7 is sent to the nozzle 8
◎ The piezoelectric element 9 contracts when energized, and the ink 1 in the nozzle 8
0, and this pressure causes the ink to flow through the ejection port 11.
It is ejected as droplets.

A cartridge ink tank 12 is removably attached to the upper surface of the ink tank 7, and ink 10 is supplied to the ink tank 7 from a passage in the attachment part.

Further, a thin tube 13 is provided on the bottom surface of the ink tank 7 to communicate the inside of the ink tank 7 with the outside air.

The inner diameter of the thin tube 13 needs to be set to such an extent that the ink 10 does not fall by itself. For example, the viscosity of ink 10 is 5.
5 a, p, and a surface tension of 50 dyn@,/m, the inner diameter of the thin tube 13 may be from 0.1 to 4 [■], preferably from 0.3 to 2.5 [squares]. If the inner diameter is larger than that, ink will constantly leak.

With this configuration, an ink meniscus is formed within the thin tube 13, and the ink within the nozzle 8 is always kept below atmospheric pressure.

Furthermore, when the ink 10 decreases as the ink 10 is ejected through the ejection port 11, the pressure inside the ink tank 7 decreases, and the ink meniscus inside the thin tube 13 is pushed by atmospheric pressure and rises. Outside air is introduced into the ink tank 7 as air bubbles, and an ink meniscus is formed within the capillary tube 13 (5).

In this way, the pressure inside the ink tank 7 is always maintained at a constant value below atmospheric pressure.

Refilling of the ink 10 can be easily performed using the cartridge ink tank 12.

FIG. 3 is a sectional view of a recording head in another embodiment of the invention.

In this embodiment, the entire recording head is made replaceable as a car. Therefore, the ink tank 14
There is no ventilation path other than the thin tube 13. The inner diameter and other configurations and operations of the thin tube 13 are the same as those of the previous embodiment, so their explanation will be omitted.

FIG. 4 is a perspective view showing a portion of the liquid jet recording apparatus equipped with the recording head shown in FIG. 3. FIG.

The recording head 15 is removably fixed on the carriage 2 and runs in the direction of arrow M, and the platen 3 rotates in the direction of arrow S to move the recording paper 4. The ink 10 is then ejected from the ejection openings 11 of the recording head 15 to form a desired pattern on the recording paper 4 (6). Note that it goes without saying that the recording head 15 may be the head shown in FIG. Also, by making the ink tank or the entire recording head a cartridge type, it has become extremely easy to replenish ink or replace the head.

In this embodiment, a nozzle using a cylindrical piezoelectric element 9 was used as the liquid ejecting means, but the nozzle is of course not limited to this, and as shown in FIG. It may be a nozzle that utilizes.

〔Effect of the invention〕

As described in detail above, the liquid jet recording device according to the present invention is characterized in that the liquid jetting means and the liquid container are integrated, and a sufficiently thin ventilation means is provided in the lower part of the container. By integrating the liquid ejecting means and the liquid container, the invention can be miniaturized.Furthermore, since an ink supply tube is not required, the ink ejection characteristics are stable and the quality of the recording result is improved. Improve.

Further, by providing a sufficiently thin ventilation means in the lower part of the container, the inside of the ink container can be maintained at a substantially constant pressure below atmospheric pressure, and leakage of ink from the discharge port can be prevented.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a part of a conventional liquid jet recording device, FIG. 2 is a sectional view of a recording head in a first embodiment of the present invention, and FIG. 3 is a cross-sectional view of a recording head in a second embodiment of the present invention. A sectional view, FIG. 4 is a perspective view showing a part of the second embodiment, and FIG. 5 is a partial sectional view showing another example of a nozzle for ejecting liquid. 7.14... Ink tank, 8... Nozzle, 9...
・Piezoelectric element, 10... Ink, 11... Discharge port, 1
2... Cartridge ink tank, 13... Thin tube,
16...Electrothermal converter. '@ 5 Figure 'l) A! Q-

Claims (1)

[Claims] (1) In a liquid ejection recording device having a liquid ejecting means and a container containing the liquid ejected by the liquid ejecting means, a ventilation means is thin enough to prevent the liquid in the container from spontaneously flowing out into the lower part of the container. A liquid jet recording device/