JPS61235154A - Ink jet accumulator - Google Patents

Abstract

PURPOSE:To obtain an accumulator capable of maintaining reliability for a long time by using an ink layer and a non-solving liquid as materials for separating an air layer from an ink layer in an accumulator. CONSTITUTION:A non-ink solving liquid as a separation material for air and ink in an accumulator is provided on an ink layer. The required thickness of the liquid for separation provided in such a way is one enabling the blocking of ink and air contact for a long time. In addition, as a liquid for separation, any material having a low vapor pressure and not allowing itself to be dispersed in the air is acceptable. In positive terms, the liquid should preferably be an oily one when water-soluble ink is used. However, if oily ink is used, the separation liquid should preferably be water-based and of low vapor pressure. Thus an accumulator capable of maintaining high reliability for a long time is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a so-called charge-controlled inkjet printer that obtains an image by controlling the charge of ink droplets continuously ejected from a nozzle and deflecting them, and particularly relates to an inkjet accumulator used in the above-mentioned inkjet printer. It is something.

Charge-controlled inkjet uses a pump to eject ink under pressure, but if there is a pulsation in the ejection pressure, the flow velocity of the ink ejected from the nozzle will fluctuate, resulting in fluctuations in the amount of deflection of ink droplets. Hekimatsugo 1 ink nakari - 3 shi ruru lψsu - [r 7 small certificates 9 In order to take 9, a room called an accumulator is provided in contact with the air, and air compression is used to reduce the pulsation of the ink pressure. ing. If ink and air are brought into direct contact under pressure, air will be mixed into the ink little by little, and eventually the air will disappear and the ink will no longer function as an accumulator. Therefore, conventional methods have been to use a bellows to expand and contract the ink, or to put a float in a cylinder to separate it from the ink. However, in the former case, the bellows expands and contracts significantly due to the application and release of ink pressure, which fatigues the material of the bellows diaphragm, leading to breakage. In the latter case, it is necessary to provide a gap between the inner wall of the cylinder and the float in order to move the float smoothly, but air comes into contact with the ink through this gap, and it is inevitable that the air will dissolve in the ink. .

An object of the present invention is to provide an accumulator that is highly reliable over a long period of time, and is characterized in that it uses a liquid as a float.

The figure is a sectional view showing one embodiment of the present invention. Ink flows from inlet 1 in the direction of the arrow, enters and exits the accumulator, and heads to outlet 2. Air is accumulated in the upper part 3 inside the accumulator, and the air is accumulated above the shaded area. In this example, the volume of air above the accumulator is 7cc (5QI(
The present invention, which uses the pulsating pressure of a pump that is driven by Z and discharges 1.600 kg per minute, is constructed by providing a liquid that does not dissolve in the ink on the ink layer as a separation material between the ink and air of the inkjet accumulator. . The thickness of the separation liquid provided in this manner may be sufficient as long as it blocks contact between the ink and air for a long period of time.

Further, the separating liquid may be any liquid having a low water vapor pressure and not being diffused into the air. Specifically, when a water-soluble ink is used, it is preferably oil-based, and in addition to the silicone oil shown in the examples, liquid paraffin or any other ink with low fish pressure may be used.

When the ink is oil-based, the separation liquid is preferably aqueous, and in this case also, one with low vapor pressure is desirable.

Although it is desirable that the vapor pressure of the separation liquid described above is low, even if it is high to some extent, the amount necessary to evaporate into the accumulator and form a saturated vapor pressure may be used.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of an inkjet accumulator according to the present invention. Intermediate sign. 1. Inlet 2. Outlet 3. Air 4. Ink 5.. 70-Tengu oil

Claims (1)

[Claims] In the accumulator of an inkjet printer,
An inkjet accumulator characterized in that a liquid insoluble in the ink layer is used as a material for separating the air layer and the ink layer in the accumulator.