JPH0313345A - Liquid droplet injector and injecting method for liquid droplet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a droplet ejecting device and method for discontinuously ejecting liquid as droplets, and relates to an inkjet that ejects liquid as fine droplets. The present invention provides a droplet ejecting device and a droplet ejecting device that can be used in a recording head.

<Conventional technology> Inkjet recording devices that eject ink as minute droplets to form dots on recording paper are non-impact systems, so there is no embarrassing sound, and detailed depictions can be made, and they can also be printed on plain paper. It has excellent features such as easy recording, and is used for making hard copies for facsimiles, word processor printers, etc.

The above-mentioned inkjet recording device has an opening with a diameter of about 30 to 100μ at the tip of the nozzle to form fine ink droplets, and pressurizes the ink in the nozzle to form ink from the opening in the form of droplets. It is something that makes people squirt.

(Problems to be Solved by the Invention) However, in the above-mentioned inkjet device, since the aperture of the opening is minute as described above, particles that are insoluble in the ink, such as dust, may get mixed into the ink. If some of the ink adheres to the vicinity of the opening and dries and solidifies, the direction and amount of ink droplet ejection may change, and the flow of ink may be blocked during ejection. , the reliability of print formation is low, such as ink droplets not being ejected.

In addition, ink droplets are extracted from the opening by applying pressure to the ink in the nozzle, but in the on-demand method where pressure is applied intermittently, the pressure inside the nozzle increases after the ink droplets are ejected. Air may be sucked in through the opening. Then, when the ink is pressurized next time, the sucked air obstructs the ink jetting and causes the droplets to become uneven, reducing the reliability of the print forming function.

In addition, in recent years, a method has been proposed in which ink is magnetized by adding magnetic powder to the ink, and a magnetic field is applied to the ink to jet the ink, but the ink used is extremely expensive, and furthermore, It also did not solve the problems of conventional methods.

Therefore, there has been a desire for a droplet ejecting apparatus and a droplet ejecting method that do not have the drawbacks of the conventional inkjet recording apparatuses described above and have excellent ejection stability.

The present invention has been proposed in view of the above, and includes a cylindrical nozzle, in which liquid-tight chambers surrounded by a membrane material are provided in opposing directions along the length of the cylindrical nozzle. The liquid-tight chamber is filled with a magnetic fluid, and a magnetic force generating means is provided on the outer surface of the cylindrical nozzle, consisting of a plurality of parallel solenoids controlled so that the generated magnetic field advances, and the magnetic force generating means is opposed to each other. A droplet ejecting device and a droplet, characterized in that the liquid inside the cylindrical nozzle is extracted from the tip according to the change in the shape of the membrane material by applying a traveling magnetic field to the magnetic fluid in the liquid-tight chamber. It is related to the ejection method.

<Example> Hereinafter, the present invention will be explained in detail based on the drawings.

The droplet injection device of the present invention has membrane materials 2 disposed facing each other along the length direction inside a cylindrical nozzle l, and liquid is sent out from the opposing intervals of the membrane materials 2 to the tip of the cylindrical nozzle l. It is extracted through the opening 3.

The above-mentioned cylindrical nozzle l is molded from a hard material such as non-magnetic metal or hard plastic, and the membrane material 2 is made of an extremely flexible elastic material such as rubber or soft plastic. This method uses rubber or composite materials that combine these elastic materials and fibers.

A liquid-tight chamber 4 is formed between the above-mentioned cylindrical nozzle 1 and the membrane material 2, and this liquid-tight chamber 4 is filled with a magnetic fluid 5. Further, on the outer surface of the above-mentioned cylindrical nozzle 1, magnetic force generating means 7, which is formed by arranging a plurality of solenoids 6 in parallel, is provided for each liquid-tight chamber 4.

Each solenoid 6 of this magnetic force generating means 7 has a cylindrical nozzle l.
The magnetic field is electronically and electrically controlled so that the magnetic field generated from the opening rear end 8 to the opening front end 3 advances in sequence.

Therefore, each solenoid 6 of the opposing magnetic force generating means 7
When the magnetic field generated from the liquid-tight chambers 4 is made to proceed with different polarities, the apparent specific gravity of the magnetic fluid in each liquid-tight chamber 4 increases partially, and the membrane material 2
A part of the nozzle 1 is deformed inward and becomes a protrusion, and this protrusion moves from the rear end 8 of the opening toward the tip 3 of the opening as the magnetic field advances, so that the opposite membrane material 2 The fluid within the interval is pushed out by the movement of the protruding portion, and is ejected from the opening tip 3 in the form of droplets.

Moreover, if each magnetic force generating means is electrically controlled with high precision to instantaneously generate and advance intermittently, the opening tip 3
Droplets will be ejected continuously.

Therefore, according to the present invention, when ink is used as a fluid between the facing spaces of the membrane material 2, the ink is continuously ejected in the form of droplets from the opening tip 3 of the nozzle 1, and the ink ejection state progresses. Although it varies depending on factors such as the frequency and strength of the magnetic field, the magnetization of the magnetic fluid in the magnetic field, the thickness of the magnetic fluid in the direction of the magnetic field, and the flexibility of the film material 2, the amount of ink ejected in an inkjet recording device depends on the frequency and magnetic field. It is most effective to control the intensity of the

Further, as shown in FIG. 3, the tip opening 3 of the cylindrical nozzle l
In this process, a constant magnetic field is applied to the opposing solenoid 4 to form a reduction part 9 that narrows down the ink flow path area in the nozzle 1, and the ink jetting speed and jetting response are controlled by turning on and off the application of the steady magnetic field. Not only can it be improved (it can form a proper droplet, but it also doesn't suck air through the tip opening).

Furthermore, when the droplet ejecting device of the present invention is finished being used or is not used for a while, the opening 3 is closed by applying a steady magnetic field to the tip opening 3 to press the opposing membranes 2 together. This prevents the backflow of air and prevents the ink from drying and solidifying in the opening 3, allowing it to be immediately reused.

It should be noted that the symbols not explained in FIG. 3 have the same structure as in the above-described embodiment, so the explanation will be omitted.

Although the present invention has been described above based on the embodiments shown in the drawings, the present invention is not limited to the above-described embodiments, and can be implemented in any manner as long as the configuration described in the claims is not changed. can.

<Effects of the Invention> As explained above, when the droplet jetting device of the present invention is applied to an inkjet recording device, various drawbacks of conventional inkjet recording devices can be solved and stable print formation can be performed. It is possible.

In addition, any type of ink can be used, and it can be water-based or oil-based, so it has extremely high applicability.

Furthermore, the droplet jetting device and droplet jetting method of the present invention prevents clogging at the nozzle opening (and does not flow out even if fine insoluble particles such as dust are present in the nozzle). Therefore, it is possible to provide an inkjet recording apparatus that can form highly reliable prints without causing the ink flow path to become clogged.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a schematic vertical cross-sectional view, FIG. 2 is a vertical cross-sectional view, and FIG. 3 is a vertical cross-sectional view showing another embodiment. 1 is a cylindrical nozzle, 2 is a membrane material, 3 is a tip opening, 4 is a liquid-tight chamber, 5 is a magnetic fluid, 6 is a solenoid, and 7 is a magnetic force generating means. Figure 1 Figure 3

Claims (2)

[Claims] (1) Inside the cylindrical nozzle, liquid-tight chambers surrounded by a membrane material are provided facing each other along the length direction of the cylindrical nozzle, and the liquid-tight chambers are filled with magnetic fluid, and the outer surface of the cylindrical nozzle is In this method, a magnetic force generating means is provided in which a plurality of solenoids arranged in parallel are controlled so that the generated magnetic field advances, and by applying a traveling magnetic field to the magnetic fluid in the opposing liquid-tight chamber by the above-mentioned magnetism generating means, the film material is A droplet ejecting device characterized in that liquid inside a cylindrical nozzle is made to drip from the tip according to a change in shape. (2) Inside the cylindrical nozzle, liquid-tight chambers surrounded by an extremely flexible film material are provided facing each other along the length of the cylindrical nozzle, and the liquid-tight chambers are filled with magnetic fluid. A magnetic force generating means is provided on the outer surface of the shaped nozzle, and the magnetic force generating means is formed by arranging a plurality of solenoids that are controlled so that the generated magnetic field advances, and the aforementioned magnetic force generating means acts on the magnetic fluid in the opposing liquid-tight chamber. A droplet jetting method characterized in that the liquid inside the cylindrical nozzle is dripped from the tip according to the change in the shape of the membrane material.