JP2003326746A - Ink supply path for inkjet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent an ink from dripping from an ink supply path when an ink tank is attached/detached in an inkjet recorder of an ink tank replacement type. <P>SOLUTION: The ink tank, a negative pressure generating mechanism and an inkjet head are connected by the ink supply path. In the ink supply path, a mechanism is set for guiding a free ink to a different place by conducting a negative pressure to an ink channel between the ink tank and the negative pressure generating mechanism through an operation of separating the ink tank. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus having an ink tank for storing ink and an ink supply system for an ink jet recording apparatus having an ink jet head for ejecting ink. The present invention relates to an ink supply system capable of supplying ink by exchanging the ink.

[0002]

2. Description of the Related Art In an ink jet recording apparatus, an ink jet head (for ejecting ink), a negative pressure generating portion for supplying ink to the ink jet head to generate a negative pressure, an ink tank (ink for ink storage) The ink supply system consisting of the ones to be replaced when the ink is exhausted) and the ink supply path for circulating the ink between them and the ink tank and the entire system are jointed. To prevent dripping, a needle is placed on the side of the ink supply path that comes from the head, and a rubber stopper is placed on the ink tank side. Has been achieved and commercialized. However, in recent years, with the increase in the number of nozzles of the inkjet head and the increase in the driving frequency, one having a large ink supply performance has been demanded. In the above system, the ink flow rate is limited due to the diameter of the needle and the like, and therefore an ink supply system that secures the flow rate is required. In order to increase the ink supply amount, it has become necessary to increase the diameter of the joint portion. In that case, it was necessary to establish a pipe-to-pipe fitting, rather than a needle-rubber combination. At this time, the problem is to prevent the residual ink remaining in the joint portion from leaking to the outside. Specifically, it is how to treat the free ink in the ink tank from the negative pressure generating chamber when the ink tank is replaced.

Actually, it is not only necessary to replace the ink in the ink tank when all the ink is used up. Therefore, assuming the case where the ink is replaced in the ink tank, the joint side inside the ink tank is sealed. It is necessary to install a valve. Therefore, it is conceivable that the free ink in the sealed ink supply passage at the time of exchanging the ink tank is pulled out from the joint passage when the ink tank is pulled out.

[0004]

SUMMARY OF THE INVENTION According to the present invention, when the ink tank is attached and detached while ensuring the ink flow rate in the ink path connecting the ink tank and the negative pressure generating chamber, the ink tank and the negative pressure generating section are separated from each other. An object is to prevent the free ink existing in the flow path between them from leaking to the outside.

[0005]

The ink existing between the ink tank and the negative pressure generating chamber is provided with an ink suction mechanism that operates by detaching the ink tank, so that the free ink when the ink tank is detached is installed. It is possible to reduce the probability of leaking to the outside by promptly sucking those that have become. Further, by providing a backflow prevention mechanism in the ink suction mechanism, it is possible to prevent ink from being blown out when the ink tank is attached.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION (First Embodiment) The embodiment of the present invention has the configuration shown in FIG.

First, the structure before carrying out the present invention is shown in FIG.

An ink tank for storing ink and a negative pressure generating chamber for applying a negative pressure to the head are connected by a tubular ink supply passage which is sealed when the ink tank is inserted. Further, the negative pressure generating chamber is composed of a negative pressure generating member and a negative pressure generating chamber container, and supplies ink to the inkjet head via a filter for the negative pressure generating member, separately from the ink supply path from the ink tank.

However, the ink tank has a built-in mechanism that is opened at the same time when the ink supply path A and the ink supply path B are fitted together. The mechanism here is an ink tank valve that is arranged to be pushed in at the end of the ink supply path A, and releases the ink tank at the same time that it is installed. When removing the ink tank, simply slide the ink tank, and the ink tank The valve seals the inside of the ink tank.

When exchanging the ink tank with this structure, the operation of pulling out the ink tank while rotating it is performed. At that time, the valve inside the ink tank is closed, and then the ink supply paths A and B are separated and communicated with the atmosphere. Until just before communication with the atmosphere, the volume in the ink supply passage expands, so that a force for drawing out the ink from the negative pressure generating chamber is generated. Therefore, depending on how the ink tank is replaced, the ink may drop from the ink supply path A extending from the negative pressure generating chamber.

Next, a description will be given of the ink supply passage of the present invention to which a mechanism for applying a negative pressure is added (see FIG. 2).

By removing the ink tank,
The ink tank valve inside the ink tank is completely sealed,
Next, a part of the ink supply path constituted by the ink flow paths A and B is exposed to the atmosphere. At that time, at the same time, the suction pump arranged at the bottom of the ink tank operates by the operation of removing the ink tank, and a negative pressure is generated inside the suction pump. This angular pressure releases the valve 1 in the ink suction passage and closes the valve 2, and the negative pressure of the suction pump directly acts on the ink passage constituted by the ink iron supply passages A and B. However, even when the ink tank was removed, it was possible to reduce the probability of the ink dripping outside by guiding the free ink to the suction pump after being released to the atmosphere.

Next, when inserting new ink, the ink tank is operated so that the inside of the suction pump is pressurized,
As valve 1 closes, valve 2 opens. As a result, the ink stored inside the suction pump returns the ink to the negative pressure generation chamber through the ink return flow passage, and the ink sucked from the ink supply passage is returned to the negative pressure generation chamber without being wasted for use. be able to.

After that, the ink supply path A and the ink supply port B on the ink tank side are fitted together, and finally the valve in the ink tank is opened, whereby the mounting of the ink tank is completed.

By performing the above operation, it is possible to reduce the dripping of the free ink in the ink supply passage due to the attachment / detachment of the ink tank.

[0016]

According to the present invention, by providing a mechanism for generating a negative pressure for sucking ink in the ink flow path between the ink tank and the negative pressure generating chamber, the free ink generated when the ink tank is detached and attached. Was able to move to another part.

Therefore, when the ink tank is attached and detached, the amount of ink flowing out from the ink flow path can be greatly reduced.

[Brief description of drawings]

FIG. 1 shows the structure before implementing the present invention.

FIG. 2 is an embodiment of the present invention.

[Explanation of symbols]

1 inkjet head 2 Negative pressure generating member 3 Negative pressure generation chamber 4 Ink supply path A 5 Ink supply range B 6 ink tank 7 spring

Claims (6)

[Claims] 1. An ink-jet ink supply system in which an ink tank, a negative pressure generating means, and an inkjet head are connected by an ink flow path, wherein the ink tank is a detachable ink supply path. An inkjet ink supply path provided with an ink suction mechanism connected to the ink flow path between the tanks. 2. The inkjet ink supply passage according to claim 1, wherein a portion that is connected to the ink suction mechanism and applies a negative pressure to the ink supply passage is in the ink supply passage inside the ink tank. 3. The ink jet printer according to claim 2, wherein the portion that applies a negative pressure in the ink supply passage acts on a portion where the ink flow passage is exposed to the atmosphere when the ink tank is attached and detached. Ink supply path. 4. The ink supply path for inkjet according to claim 1, wherein a backflow prevention mechanism is arranged in the ink suction mechanism. 5. The ink supply path for an ink jet according to claim 1, wherein an ink suction mechanism that operates by attaching and detaching an ink tank is used. 6. The ink-jet ink supply path according to claim 1, wherein the ink discharge side of the ink suction mechanism is connected to the negative pressure generating means.