JPH01209147A - Ink jet recording apparatus - Google Patents

Abstract

PURPOSE:To simplify handling by eliminating trouble or maintenance, by providing a collecting plate on the way of an air flow passage to trap ink mist and automatically discharging said mist. CONSTITUTION:The mist suction unit 7 on an ink jet head module 2 is connected to an air suction means by a suction pipe during recording to be held under negative pressure. Therefore, the air stream in the vicinity of a mist sucking unit suction port 71 flows toward the interior of the mist suction unit 7 and ink mist 5 is also sucked in said unit 7. The greater part of the sucked ink mist is stuck to the inner wall of the mist suction unit 7 or stuck to the barrier plate 76 at the back of said unit 7 to be accumulated in a mist sump 77. A one-way valve 3 is closed because of negative internal pressure and an image is drawn before long and an air suction means is stopped and, when the pressure in the ink mist suction unit 7 is returned to atmospheric pressure, the valve 3 becomes an open state and the liquid in the ink sump 77 is discharged out of the unit through a drain pipe 4.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an inkjet recording apparatus equipped with a collection box for collecting ink mist from an inkjet head used in color printers, computer terminals, and the like.

BACKGROUND TECHNOLOGY In a conventional inkjet recording apparatus of this type, 2.
＼.

Japanese Patent Application Laid-Open No. 62-55148 has already proposed a method for collecting ink that does not adhere to the recording medium but bounces or floats during ink ejection during drawing.

That is, the idea is to use a suction box to collect the ink mist that bounces off near the inkjet head that ejects ink using a suction filter.

Problems to be Solved by the Invention However, with such a structure, the inhaled mist either attaches directly to the filter and is collected, or it attaches to the inner wall of the box, flows along the wall, and is collected by the filter. It will be one of two things. In addition, when the dirt becomes strong, maintenance is not easy, as the only option is to remove it and replace it each time, or to flush it with water.

This is due to the following reasons.

Figure 2 shows a state in which the mist suction unit 7 is attached to the inkjet head module 2. The inkjet head module 2 includes the inkjet head 1, head guide plates 10 and 3, \-7, ink containers, tubes, and signal lines. It consists of etc. The mist suction unit 7 includes a housing 74 and a filter 7.
3, and is connected to a suction means 9 through a suction pipe 8.

Most of the ink ejected by the inkjet head 1 adheres to the recording medium 6, but the ink that cannot adhere bounces back and becomes a mist 75 and floats. Then, since the inside of the mist suction unit 7 is under negative pressure, the ink mist is sucked in. Then, these droplets hit the inner wall, grow together with the liquid, and are captured by the filter 73.

However, with this method, it is impossible to know when to replace or clean the filter, which can be determined from the outside, and even if it could be known, it would have to be removed from the inkjet head module 2 each time, which would be a hassle. Therefore, the present invention aims to eliminate the need to discard each time even if a large amount of ink mist is collected, and to minimize the amount of ink mist that is collected, thereby simplifying the handling of the ink mist. .

Means for Solving the Problems and Technical Means of the Invention for Solving the Problems mentioned above are to provide a baffle plate in a part of the mist suction unit that collects ink mist and which will become a passage for the mist, and to bring the inside of the mist suction unit to atmospheric pressure. When this happens, the liquid that has collected in this mist will automatically flow out.

For production The effect of this technical means is as follows.

In other words, the method of sucking ink liquid, which is an aggregate of ink mist, into a filter and taking it out to clean or replace it takes time and reduces the operating rate of the machine. It also shortens the life of the filter. By installing a collection plate made of common materials that is not eroded by ink, as in the present invention, and periodically draining the collected liquid, it is possible to extend the life of the parts and make the device work more efficiently. 05 \-7 Example An example of the present invention will be described below based on the accompanying drawings.

In FIG. 1, reference numeral 7 denotes a mist suction unit, which is installed on top of the inkjet module 2. The mist suction unit 7 is composed of a baffle plate (collection plate) 76 that collides with and collects the ink mist 75, a valve 3 that drains the accumulated liquid, a drain pipe 4, and a housing 74.

Next, the operation of the configuration of this embodiment will be explained. A description will be given of the process by which the ink mist 75 is generated, sucked in, and discharged.

As shown in FIG. 2, the inkjet head module 2 and the recording medium 6 are arranged facing each other.

The recording medium 6 is wound around a cylindrical drum 5, the drum 5 rotates, and the inkjet module 2 moves parallel to the central axis of the drum to form a single plane image.

Ink ejected from the inkjet head 1 adheres to the recording medium 6. However, the degree of adhesion of ink varies depending on the conditions on the recording medium, such as humidity and the amount of ink to be ejected, which naturally causes some ink to splatter. This is called ink mist 75, which has a very small particle size and is light, and floats on the surface of the recording medium.

On the other hand, the inside of the mist suction unit 7 on the inkjet head module 2 is connected to an air suction means 9 through a suction pipe 8 and is under negative pressure. Therefore, the airflow near the mist suction unit suction lower 1 flows toward the inside of the mist suction unit 7. That is, the air near the opening is being sucked in, and the ink mist 75 is also being sucked in. Most of the sucked ink mist adheres to the inner wall of the mist suction unit 7 or to the baffle plate 76 at the back. When a considerable amount of ink mist 75 adheres, it grows into droplets, and when further sucked, it becomes liquid and accumulates in a mist reservoir 77. At this time, the one-way valve is in a closed state because the internal pressure is negative. Next, when an image is drawn, the air suction means 9 stops, and the pressure inside the ink mist suction unit 7 returns to atmospheric pressure, the restoring force of the valve 3 acts to open the valve. The valve 3 is set in advance by applying a force to open it slightly at atmospheric pressure, so that it will move immediately under a slight pressure. Further, this valve may be a resilient object, and the same effect can be obtained even if a check valve or the like is provided in the middle of the drain pipe 4 in place of this valve structure. When this valve opens, the liquid in the ink reservoir 77 is discharged to the outside of the unit through the drain pipe 4. drain pipe 4
There may be a liquid receiver or a liquid receiver at the end. In this way, the ink mist is collected and discharged.

In this embodiment, the mist suction unit 7 is attached to the upper part of the ink jet module 2, but the same effect can be obtained even if it is attached to the lower part.

Effects of the Invention The present invention traps ink mist by installing a collection plate in the middle of the air flow path and automatically discharges it, which saves time and effort, and eliminates trouble and maintenance since there is no unnecessary work. This has the effect of increasing operating time.

[Brief explanation of the drawing]

FIG. 1 is an internal structural diagram of an ink jet recording apparatus according to an embodiment of the present invention, and FIG. 2 is a partial sectional view showing a cross section of a conventional ink mist suction unit and the positional relationship of a drum. 2. inkjet head module, 3. Valve, 7...
Mist suction unit, 71 Mist suction port, 76...
baffle board.

Claims (1)

[Claims] An air flow with openings in the same direction as the ink ejection ports is installed in a part of the periphery of the inkjet head module, which uses pressure waves generated in response to electrical signals to stop the ejection of minute ink droplets to form images on the recording medium. An inkjet recording device comprising: a wind tunnel through which unnecessary ink flows; a convex collecting plate inside the wind tunnel; and a discharge port having a one-way valve so that the pressure inside the wind tunnel operates at atmospheric pressure and draining unnecessary ink.