JPH045547B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Technical Field of the Invention The present invention relates to an inkjet head of an inkjet recording device, and more particularly to an inkjet recording device in which ink clogging of the inkjet head does not occur.

(B) Background of the Technology In recent years, inkjet recording devices have been frequently used in office automation equipment because they are noiseless, compact, and can use ordinary recording paper.

(C) Prior Art and Problems Figure 1 shows a block diagram of the ink supply and ink ejection system of an inkjet recording device that has been commonly used in the past.

In the figure, first, the ink 2 sucked by the pump 1 passes through the filter 3 to remove dust.
The inkjet head 4 is guided through a supply pipe 5.

Next, the ink 2 is ejected from the nozzle hole at the tip 6 of the ink jet head 4, and the ink particles 7
becomes. However, if the inkjet recording device is left in the stopped state for a long time, the liquid component in the ink 2 will evaporate and a solid component will remain, which will block the small nozzle hole, which is generally a few plus microns in diameter, and cause the inkjet recording device to start up again. However, the ink particles 7 may not be ejected, resulting in an unrecordable state.

(D) Object of the Invention In view of the above-mentioned drawbacks, it is an object of the present invention to realize an inkjet recording device that does not cause ink clogging in the nozzle holes of the inkjet head.

(E) Structure of the Invention The purpose of this invention is to provide an inkjet recording device that performs printing by jetting ink particles from a nozzle onto a recording medium, and which uses powder made of a thermoplastic resin that melts when heated. It is a cylindrical container for holding ink, and a nozzle is provided at the tip of the container, and the powder ink contained in the container is constantly directed toward the nozzle from the rear of the container. an elastic body for urging; a laser that operates in response to a command pulse for heating the nozzle portion so as to melt and liquefy the powder ink only in the vicinity of the nozzle portion; and a laser beam from the laser. A cylindrical cylinder is disposed around the container near the nozzle part except for the part to which the irradiation is applied, and is used to apply vibration to the vicinity of the nozzle part in order to cause the liquefied ink to fly out as droplets from the tip of the nozzle. A piezo vibrator is disposed on the back surface of the recording medium in order to charge the liquefied ink and to attract and fly the charged ink toward the recording medium by electrostatic force. a power source for applying a voltage between the target electrodes; a horizontal electrode and a vertical electrode disposed between the nozzle and the recording medium for controlling the flying direction of the ink droplet ejected from the nozzle;
This is achieved by an inkjet recording device characterized by comprising:

(F) Examples of the invention The present invention will be explained in detail using the drawings.

FIG. 2 is a schematic diagram of an ink jet recording apparatus according to the present invention.

In the figure, 8 is a powder ink 9 (particle size 10
9 is a stainless steel pipe with a diameter of about 100 [μm] filled with 20 [μm]), and powder ink 10 made of thermoplastic resin is a glass nozzle with a hole diameter of about 50 [μm] attached to the tip of the stainless steel pipe 8. , 11 is a cylindrical piezo vibrator arranged around the stainless steel pipe 8, 20 is an oscillator that applies a pulse voltage to the cylindrical piezo vibrator 11, and 12 is a cylindrical piezo vibrator that presses the powder ink 9 inside the stainless steel pipe 8 from the rear end. , a spring that gradually advances the powder ink 9; 13, a lens that focuses the laser beam from the laser 15 so that it is focused on the glass nozzle 10; and 14, a command pulse that causes the laser 15 to generate the laser beam during printing. 15 is a laser that melts the powder ink 9 in the stainless steel pipe 8 to form liquid ink 9'; 16 is a target electrode;
17 and 18 are horizontal and vertical electrodes that control the flying direction of the liquid ink 9', and 19 is a sheet of paper.

Next, the operation of this embodiment will be explained.

First, a command pulse from the control section 14 causes the laser 15 to generate a laser beam. The powder ink 9 in the glass nozzle 10 is melted by the laser beam from the laser 15, and becomes liquid ink 9' as shown in FIG. This liquid ink 9' is applied to the glass nozzle 1.
It is held at the tip of 0 by surface tension.

After the laser beam irradiates the powder ink 9 (several [μs] to several [ms]), that is, after the powder ink 9 turns into liquid ink 9', the cylindrical piezoelectric vibrator 11
When a pulse voltage from the oscillator 20 is applied to
The liquid ink 9' flies from the tip of the glass nozzle 10 in the form of ink particles 7. Here, by applying a voltage between the stainless steel pipe 8 and the target electrode 16, the liquid ink 9' is charged. Therefore,
The liquid ink 9' ejected from the tip of the glass nozzle 10 advances toward the target electrode. The flying direction of this liquid ink 9' can be controlled by a horizontal electrode 17 and a vertical electrode 18 provided at the tip of the glass nozzle 10.
You can print by placing .

As explained above, according to the present invention, powder ink is melted by a laser at the tip of a glass nozzle,
Since it is sufficient to jet the ink after it has been made into liquid ink, there is no need for clogging at the nozzle ejection port.

It should be noted that it is sufficient to use any type of laser, such as He-Cd, Ar, or semiconductor laser, as long as it has a power of about 1 [mW].

Furthermore, if a thermal head is used in place of a laser, the device can be made smaller.

Further, in the embodiments of the present invention, an inkjet recording device using powder ink has been described, but the present invention is not limited to this.
It goes without saying that the same effects as in the above-mentioned embodiments can be obtained even if a liquid ink impregnated with a thermoplastic resin is used.

(G) Effects of the Invention According to the present invention, since the ink is melted when ink is ejected, an inkjet recording device that does not become incapable of printing due to ink clogging can be provided.

In addition, since the ink is heated only near the nozzle, the solid ink will not be heated for a long time and will not change in quality (change in viscosity, etc.) or change color.
It becomes possible to realize a highly reliable inkjet recording device.

Furthermore, since there is no need to consider leakage of liquefied ink to the ink holding portion, the means for transporting the solid ink can be simplified.

Further, by using the molten ink, it is possible to obtain high fixability and high print quality due to the ink soaking into the recording paper.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a conventional inkjet recording apparatus, FIG. 2 is a schematic block diagram of an inkjet recording apparatus according to the present invention, and FIG. 3 is an enlarged view of the tip of the glass nozzle in FIG. 2. In the figure, 1
is a pump, 2 is an ink, 3 is a filter, 4 is an ink jet head, 5 is a supply pipe, 6 is a tip, 7 is an ink particle, 8 is a stainless steel pipe, 9
9 is a powder ink, 9' is a liquid ink, 10 is a glass nozzle, 11 is a cylindrical piezo vibrator, 12 is a spring, 13 is a lens, 14 is a control unit, 15 is a laser, 16 is a target electrode, 17 and 18 are Horizontal and vertical electrodes, 19 are sheets of paper.

Claims (1)

[Scope of Claims] 1. An inkjet recording device that performs printing by jetting ink particles from a nozzle onto a recording medium, which holds powder ink made of a thermoplastic resin that melts when heated. A cylindrical container for use in the container, the tip of the container being provided with a nozzle, for constantly urging the powder ink contained in the container toward the nozzle from the rear of the container. an elastic body; a laser that operates in response to a command pulse for heating the nozzle portion so as to melt and liquefy the powder ink only in the vicinity of the nozzle portion; and a laser beam irradiated by the laser. a cylindrical piezoelectric vibrator disposed around the container near the nozzle section except for a portion thereof, and for applying vibration to the vicinity of the nozzle section in order to cause the liquefied ink to fly out as a droplet from the tip of the nozzle; In order to charge the liquefied ink and to attract and fly the charged ink toward the recording medium by electrostatic force, a target electrode is disposed on the back surface of the recording medium, and a target electrode is arranged between the container and the target electrode. a power supply for applying a voltage to the nozzle; and horizontal and vertical electrodes disposed between the nozzle and the recording medium to control the flying direction of ink droplets ejected from the nozzle. An inkjet recording device characterized by: