JPH03286876A - Ink cartridge for ink jet printer - Google Patents

Abstract

PURPOSE:To make it possible to inhibit air and printing ink in an ink tank housing an impregnation member from being agitated by reciprocating motion of a carriage, by forming a partition member in an ink chamber for taking off the ink from the ink tank. CONSTITUTION:In the process of feeding ink, air may enter to an ink chamber 12 before the ink is completely consumed, air in the ink chamber 12 usually stays at an upper portion of the ink chamber 12 by its buoyant force. But, if reciprocal motion of a carriage 2 is violent, in other words, the motion of the carriage 2 is high speed mode, the ink has agitated contact with air in the ink chamber 12. But, since a partition member 13 is formed in a center portion of the ink chamber 12, the agitated contact is inhibited and air is prevented from flowing toward a printing head 3 from the ink chamber 12.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink jet recording apparatus that records characters, etc. on a recording medium by ejecting ink droplets from a nozzle, and particularly relates to an ink cartridge for supplying ink.

[Conventional technology]

2. Description of the Related Art Various ink supply means have been proposed and put into practical use in ink sheet recording apparatuses that record characters and the like on a recording medium by ejecting ink droplets from nozzles. In particular, this is common in ink cartridges or small ink jet recording apparatuses configured to supply ink sealed in a flexible bag by inserting an ink needle through a sealing member such as rubber. The above-mentioned ink cartridge packed with a flexible bag is generally not configured to move along the recording medium along with the print head on the carriage, but is fixed inside the recording device, and the ink is transported on the carriage through a flexible tube or the like. Supplied to the print head. However, the above fi
The ink supply system is complicated, the volumetric efficiency is poor, and the cost is high.

Of course, to deal with this problem, it would be possible to mount the ink cartridge on a carriage, but if the ink cartridge made of the aforementioned flexible bag is mounted on the carriage, there will be problems with the durability of the bag. Moreover, there is a problem that the volumetric efficiency is poor and the carriage becomes larger than necessary. Furthermore, in order to deal with such problems, ink cartridges have been proposed in which an ink tank containing a porous material or the like is impregnated with ink and is mounted on a carriage. A cylindrical ink chamber was provided at the bottom of the ink tank in order to efficiently take out the ink inside the ink tank.

[Problem to be solved by the invention]

In this type of ink cartridge for an inkjet recording device, during the process of taking out ink from the ink tank, air flows into the ink chamber from the ink tank side, and eventually the ink runs out. The ink flows into the ink chamber before the ink reaches the end state.

In reality, ink is taken out from the ink tank while the incoming air remains in the upper part of the ink chamber due to its buoyancy. Furthermore, in an inkjet recording device in which an ink cartridge is mounted together with a head on a carriage, the air that has flowed into the ink chamber described above is agitated within the ink chamber in response to the reciprocating movement of the carriage. If the agitation is intense, air flows into the print head side against the buoyancy during normal printing operations, resulting in problems such as printing defects and other deterioration in reliability.

[Means to solve the problem]

The ink cartridge of the present invention is characterized in that it has an ink tank containing an ink-impregnated member and an ink chamber communicating with the bottom of the ink tank, and a partition member is formed in the ink chamber.

[For production]

With this configuration, even if the carriage moves back and forth with ink and air mixed in the ink chamber, the partition member formed in the ink chamber suppresses agitation of the ink and air. Due to its buoyancy, air can always remain stably in the upper part of the ink chamber, thereby preventing air from flowing into the print head from the ink chamber before the ink in the ink tank is exhausted.

〔Example〕

To explain the present invention based on the drawings, FIG. 1 shows an embodiment of an inkjet recording apparatus configured using the ink cartridge of the present invention, and shows a platen 1.
A print head 3 is integrally provided in the carriage 2 that reciprocates along the platen 1 in the vicinity of the platen 1, and a form 7, which is an ink-impregnated member made of a porous material such as polyurethane foam, is installed inside the carriage 2 at the rear thereof. An ink tank 8 containing the ink is provided. This ink tank 8 is provided with a vent hole 10 in its lid 9 to allow atmospheric air to be taken in, and a platform-shaped protrusion 11 is formed on the bottom surface of the ink tank 8 to ensure close contact with the form 7. An ink chamber 1 that takes out ink from the form 7 downward from the center and holds it there.
In the ink chamber 12, a partition plate 13 serving as a partition member is formed so as to be perpendicular to the direction of reciprocating movement of the carriage. FIG. 2 shows a diagram of the ink chamber 12 viewed from the platform-shaped protrusion 11 side. Furthermore, this ink chamber 12 has a communication hole 15 extending from its lower end in the direction of the head 3.
The end of the communicating hole 15 is sealed with a sealing member 14 made of an elastic material such as rubber, and the ink is connected to the sealing member 14 through the filter chamber 4 to the print head 3. By inserting the needle 5, the ink tank 8
It is configured to supply the ink impregnated therein to the print head 3. The ink chamber 12 and the communication hole 15 are integrally formed, and the sealing member 14 and the foam 7 form a sealed chamber.

Next, the process of supplying ink from the foam 7 housed in the ink tank 8 to the ink chamber 12 will be explained with reference to FIG.

When the form 7 is brought into pressure contact with the platform 11 which is the upper part of the ink chamber 12 whose upper end serves as the ink outlet from the ink tank 8, the ink impregnated into the form 7 will be released into the ink chamber 12. The consumed amount is sequentially supplied into the ink chamber 12 by capillary action to fill the ink chamber 12 (FIG. 3(a)). As the ink consumption continues,
As the ink in the form 7 gradually depletes, a part of the air J that replaces the ink and enters the form 7 reaches the bottom of the form 7 while encountering great resistance, and reaches a part of the ink outlet. I started to show my face. When ink consumption progresses to this point, a partial break occurs between the ink in the form 7 and the ink in the ink chamber, which were communicating at the ink outlet (FIG. 3(b)). Even in this state, air is difficult to flow into the ink chamber 12 due to the flow resistance of the air against the foam 7 and the buoyancy of the air due to the fact that the outlet is located above the ink chamber 12. . Even if the air were to flow in, it normally remains above the ink chamber 12 due to the buoyancy of the air. As the ink in the form 7 is further depleted, the ink in the form 7 and the ink in the ink chamber 12 are finally separated, and the ink in the ink tank 8 reaches an end state (FIG. 3(C)).

During the ink removal process using the above-mentioned FIGS. 3(a) to 3(C), the air that has flowed into the ink chamber 12 before the ink in the ink tank 8 reaches the end state usually flows into the upper part of the ink chamber 12 due to its buoyancy. However, when the carriage 2 makes a vigorous reciprocating motion, such as in a so-called high-speed mode, the ink and air are stirred in the ink chamber 12. However, the second
As shown in the figure, a partition plate 1 is placed in the center of the ink chamber 12.
3, the above-mentioned agitation is suppressed and air does not flow into the print head 3 from the ink chamber 12 against its buoyancy.

Further, in this embodiment, the partition plate 13 and the ink chamber 12 are made of plastic and are integrally formed, so that the cost is not increased at all.

According to experiments, when the inner diameter of the ink chamber 12 is 10111 mm, it was possible to obtain the desired effect by forming one partition plate 13 in a direction perpendicular to the reciprocating direction of the carriage 2.

FIG. 4 is a diagram showing another embodiment of the partition member of the present invention, and is a diagram of the ink chamber 12 viewed from the platform-shaped protrusion 11 side. In the above-mentioned embodiment, the desired effect could be obtained with only one partition plate 13, as shown in FIG.

It goes without saying that when a greater effect of the partition plate 13 is required and when the opening diameter of the ink tank 8 is large, the shape of the partition member as shown in FIG. 4 is effective.

It goes without saying that the effects of the present invention can be obtained even if the height position of the side surface of the form 7 of the partition member is at the upper circumferential surface of the table-shaped protrusion 11.

〔Effect of the invention〕

As described above, according to the present invention, even if ink and air are mixed in the ink chamber due to the formation of the partition member in the ink chamber for taking out ink from the ink tank containing the impregnation member, the reciprocating movement of the carriage This makes it possible to suppress the agitation of ink and air caused by the ink tank, which prevents air from flowing into the print head from the ink chamber before the ink in the ink tank reaches its final state.
This has the great effect of providing an extremely reliable ink cartridge for an inkjet recording device at a low cost.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of an inkjet recording apparatus that is an embodiment of the present invention. FIG. 2 (a) is a view of the partition member viewed from above. FIG. 2(b) is a sectional view taken along line A-A. Figure 3(a)~
(C) is an explanatory diagram showing the supply of ink to the ink chamber. FIGS. 4(a) to 4(d) are views showing another embodiment on the partition side as seen from above.・Platen ・Print head ・Ink needle T ・Form ・Ink tank ・Protrusion ・Ink chamber 13 ・ ・ ・Partition plate or above

Claims (1)

[Claims] An ink cartridge for an inkjet recording device in which ink is taken out from an ink tank by inserting an ink needle therein, the ink cartridge having an ink tank housing an ink impregnated member and an ink chamber communicating with the bottom of the ink tank; An ink cartridge for an inkjet recording device, characterized in that a partition member is formed in an ink chamber.