JPH08197743A - Ink cartridge - Google Patents

Abstract

PURPOSE: To provide an ink cartridge capable of detecting the residual amt. of ink in an ink jet printer, simple in structure, capable of being reduced in cost to a large extent and exerting no effect on printing operation even when air bubbles are mixed with supplied ink by midway attachment and detachment. CONSTITUTION: An ink cartridge is constituted by providing a main ink chamber 51 packed with an ink absorbing element 53 absorbing and holding ink and having a venting hole communicating with the atmosphere provided to the upper part thereof and an auxiliary ink chamber 52 having a transparent part 59 formed to the outer wall thereof and communicating with the vicinity of the lower end part of the main ink chamber 51 through the communication hole 56 provided to the lower end part thereof and having an ink supply port 58 for sending out ink to an ink jet head 4 provided to the floor part thereof and hermetically closed at a part other than the floor part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink cartridge capable of detecting the remaining amount of ink in an ink jet printer or the like.

In an ink jet printer or the like, if the ink in the ink cartridge runs out during use, suddenly printing cannot be performed. Therefore, when the remaining amount of ink becomes low, it is necessary to notify the user of the state and replace the ink cartridge before the ink runs out.

[0003]

2. Description of the Related Art Conventionally, a plurality of electrodes are installed in an ink cartridge and a voltage is applied to the electrodes to detect a potential difference between the electrodes which changes when ink is reduced and air bubbles are mixed.

However, if a voltage is normally applied to the electrodes, the ink may be hydrolyzed or deteriorated, which may adversely affect the ink. Therefore, the pulse voltage is applied intermittently.

[0005]

However, in order to apply such a pulse voltage, it is necessary to provide a pulse generating circuit for the printer main body or the like, so that the controller or the like becomes complicated and the cost becomes high. There is.

Further, if the cartridge in which the ink is sufficiently left is removed for some reason, the air bubbles in the cartridge at that time are mixed into the supplied ink when the cartridge is attached next time, and the remaining amount is left. Since it causes a malfunction of the detection circuit, there is a problem that a new cartridge must be used.

Therefore, according to the present invention, it is possible to detect the remaining amount of ink with a simple structure, and it is possible to greatly reduce the cost. Further, even if air bubbles are mixed in the supplied ink due to attachment / detachment on the way, the printing operation is not affected. It is an object to provide an ink cartridge.

[0008]

In order to achieve the above object, the ink cartridge of the present invention is filled with an ink absorber for absorbing and holding ink as shown in FIG. 1 for explaining the embodiment. A main ink chamber having a vent hole communicating with the atmosphere at the top, and a transparent portion formed on the outer wall so as to communicate with the main ink chamber near the lower end through a communication hole,
It is characterized in that an ink supply port for sending out ink to the inkjet head is formed in the floor portion, and a sub ink chamber in which the other portion is sealed is provided.

It is preferable that the contact angle of the ink with respect to the inner surface of the transparent portion formed in the sub ink chamber is 30 ° or more, and a mesh is formed in the communication hole that connects the main ink chamber and the sub ink chamber. A filter should be installed.

[0010]

When the ink in the cartridge is consumed and ink is still left in the main ink chamber, if ink is sucked from the ink supply port to the inkjet head,
Ink is supplied from the ink absorber in the main ink chamber having a vent hole in the upper part, and the ink in the sub ink chamber does not decrease.

When the ink in the main ink chamber is exhausted, the ink in the sub ink chamber is sucked out from the ink supply port, and accordingly, air enters the sub ink chamber through the communication hole from the main ink chamber side, and the sub ink chamber. Gradually accumulates at the top of the.

As a result, the ink surface in the sub-ink chamber is gradually lowered, and the state can be observed from the outside through the transparent outer wall portion, so that the ink remaining amount before the ink is exhausted can be visually detected. When the contact angle of the ink with the inner surface of the transparent portion formed in the sub ink chamber is 30 ° or more, the ink surface can be easily visually recognized from the outside.

When there is ink in the main ink chamber, the ink is held at a negative pressure by the ink absorber in the main ink chamber,
When the ink in the main ink tank runs out, a negative pressure is maintained by a meniscus by a mesh filter attached to a communication hole that connects the main ink chamber and the sub ink chamber.

[0014]

Embodiments will be described with reference to the drawings. FIG.
The printing unit of the inkjet printer is shown, and the carriage 3 is reciprocally driven along a stay shaft 2 arranged in parallel with the platen 1.

The carriage 3 has a nozzle surface on the platen 1.
The inkjet head 4 is attached toward the side, and an ink cartridge 5 that stores ink to be supplied to the inkjet head 4 is detachably attached on the inkjet head 4. 6 is a lever for fixing the ink cartridge 5 to the carriage 3, 7
Is a flexible cable for transmitting a signal to the inkjet head 4.

FIG. 1 shows a state in which the ink cartridge 5 is removed from the ink jet head 4. Four
Reference numeral 1 denotes an ink ejection mechanism portion for ejecting ink droplets from the nozzle 42, which communicates with an ink supply pipe 43 protruding from the upper surface of the inkjet head 4 via an ink supply passage 44.

FIG. 2 is an exploded view of the ink cartridge 5, and the ink cartridge 5 is shown in FIG.
Will be described with reference to FIG. The ink cartridge 5 is
It is formed by a large main ink chamber 51 and a sub ink chamber 52 having the same width and height as the main ink chamber 51 and a much thinner thickness.

The main ink chamber 51 is filled with an ink absorber 53 made of a porous member for absorbing and holding ink, and a top wall having vent holes 54 communicating with the outside atmosphere is formed. A small space is formed between the two.

The sub ink chamber 52 has an internal volume of at least 0.1 cc so that the ink jet head 4 can print at least one page or more.
1 and the vicinity of the lower end portion are communicated with each other through a communication hole 56.

In the communication hole 56, the mesh filter 5
7 is attached. This mesh filter 57
Means that when the ink in the main ink chamber 51 is exhausted and the ink remains only in the sub ink chamber 52, the ink is sucked toward the inkjet head 4 side when the ink remains. A mesh having an appropriate roughness in the range of # 30 to # 800 is used so as to form a meniscus to the extent that a negative pressure equivalent to the negative pressure generated in the absorber 53 is generated. It should be noted that any member may be used instead of the mesh filter 57 as long as it can form a meniscus of the same degree.

An ink supply port 58 into which the ink supply pipe 43 of the ink jet head 4 is inserted is formed on the floor of the sub ink chamber 52, and the other part of the sub ink chamber 52 is completely sealed. There is.

When the ink ejection mechanism 41 is driven with the ink supply pipe 43 inserted in the ink supply port 58, the ink is sucked out from the ink cartridge 5 and supplied to the ink jet head 4 through the ink supply port 58. .

Inside the ink supply port 58, an O-ring 61 that closely adheres to the outer surface of the ink supply pipe 43 and seals.
A valve body 64, which is biased from the inside by the compression coil spring 63 so as to close the ink supply port 58 and opens when the ink supply pipe 43 is inserted, is housed and arranged in the cylinder body 60.

The upper end portion of the tubular body 60 is formed in a tapered shape so as to gradually narrow inward, and is arranged at a position higher than the communication hole 56. Therefore, the main ink chamber 5
1 is exhausted, and the sub-ink chamber 5 passes through the communication hole 56.
Even if the air is sucked into the inside of the nozzle 2, the air bubbles will remain in the ink supply port 58.
Instead of going to the side, it floats upward in the sub ink chamber 52.

A vertically long transparent portion 59 made of, for example, a transparent plastic material is formed on the outer wall of the sub ink chamber 52 exposed on the front side of the printer device.
Through, the ink surface in the sub ink chamber 52 can be visually recognized from the outside.

However, if the contact angle of the ink 100 in the sub ink chamber 52 with respect to the inner surface of the transparent portion 59 is not less than 30 °, it may be difficult to visually recognize the ink surface. A material having an angle of 30 ° or more is used. However, the inner surface of the transparent portion 59 may be subjected to a water repellent treatment such that the contact angle of the ink is 30 ° or more.

The transparent portion 59 extends from near the lower end to near the upper end of the sub ink chamber 52, and is graduated at appropriate intervals between them. Therefore, it is possible to accurately detect the remaining amount of ink in the sub ink chamber 52 by checking which scale position the ink surface is at.

In the apparatus constructed as described above, first, the ink is absorbed by the ink absorber 53 in the main ink chamber 51 as much as possible, and the ink is kept in the sub ink chamber 52 so that no air remains. Is filled.

While the ink in the ink cartridge 5 is consumed by the use, and while the ink remains in the main ink chamber 51, when the ink is sucked out from the ink supply port 58 to the ink jet head 4, the ink passes through the upper portion. Pore 54
Ink is supplied from the ink absorber 53 in the main ink chamber 51 which is open, and the ink in the sub ink chamber 52 does not decrease.

When the ink in the main ink chamber 51 runs out,
The ink in the sub ink chamber 52 is sucked out from the ink supply port 58, and accordingly, the air enters the sub ink chamber 52 from the main ink chamber 51 side through the communication hole 56, and the sub ink chamber 5
It accumulates on the upper part of 2. The ink is held under negative pressure by the meniscus of the mesh filter 57.

As a result, the ink surface in the sub ink chamber 52 is gradually lowered, and the state can be observed from the outside through the transparent portion 59, so that it is possible to visually detect the ink remaining amount before the ink runs out.

When the ink cartridge 5 is removed from the ink jet head 4 and reattached while ink remains in the ink cartridge 5, bubbles enter the sub ink chamber 52 from the ink supply port 58. Since it stays in the upper part of the chamber 52, it is not sucked out to the ink jet head 4 side, and problems such as dot missing do not occur.

[0033]

According to the present invention, when the ink in the main ink chamber is used up, the ink in the sub ink chamber is sucked out thereafter, and the ink surface in the sub ink chamber is gradually lowered. By observing, the remaining ink amount can be visually detected.

Therefore, it is possible to detect the remaining amount of ink with a very simple structure, and it is possible to greatly reduce the cost. Moreover, even if the cartridge is attached or detached midway, air bubbles are not mixed in the ink supplied to the ink jet head. Does not occur.

Further, by setting the contact angle of the ink with the inner surface of the transparent portion formed in the sub ink chamber to be 30 ° or more, the ink surface can be easily visually recognized from the outside.
When the ink in the main ink chamber is used up, the ink can be kept at a negative pressure by the meniscus by the mesh filter attached to the communication hole with the sub ink chamber.

[Brief description of drawings]

FIG. 1 is a side sectional view of an embodiment.

FIG. 2 is an exploded perspective view of the embodiment.

FIG. 3 is a perspective view of a usage state of the embodiment.

[Explanation of symbols]

 4 Inkjet head 51 Main ink chamber 52 Sub ink chamber 53 Ink absorber 54 Vent hole 56 Communication hole 58 Ink supply port 59 Transparent part

Claims (3)

[Claims] 1. A main ink chamber which is filled with an ink absorber that absorbs and holds ink and has a vent hole which communicates with the atmosphere and which is formed in the upper portion, and a transparent portion which is formed on the outer wall of the main ink chamber and the lower end portion. An ink characterized in that it is provided with a sub-ink chamber that is communicated with each other through a communication hole and has an ink supply port for sending ink to an inkjet head formed in the floor and the other part is sealed cartridge. 2. The ink cartridge according to claim 1, wherein a contact angle of the ink with respect to an inner surface of a transparent portion formed in the sub ink chamber is 30 ° or more. 3. The ink cartridge according to claim 1, wherein a mesh filter is attached to a communication hole that communicates the main ink chamber and the sub ink chamber.