JPH0224151A - Ink cartridge - Google Patents

Abstract

PURPOSE:To find out the remaining ink level by a simple construction by charging an ink having a different density to a recording ink in a layer form or charging an ink in a separate state until the recording ink reaches a predetermined remaining level. CONSTITUTION:A recording ink 4 is charged within a cartridge 1. A warning ink 5 having a different density and a smaller specific gravity in comparison with the ink 4 is charged on the surface of the ink 4. A joint rubber 6 is nested in the bottom of the ink cartridge 1 to depress and hold an end of a pipe 3 which connects a head 2 with the ink cartridge 1. In addition, on the upper surface of the ink cartridge 1 a hole 8 for connecting an air layer above the ink 4 to atmosphere is provided. An alternative method can be used wherein the recording ink 4 is charged in an ink bag 21, the ink bag 21 is contained in a case 20, and a thin-film ink bag 22 charged with and ink 5A different only in density is contained in the ink bag 21.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an ink cartridge that supplies ink to an inkjet recording head, and particularly relates to an ink cartridge that allows the amount of ink remaining in the cartridge to be determined.

[Conventional technology]

In an inkjet recording apparatus, a removable ink cartridge is used as an ink supply source in consideration of user operability. This ink cartridge is required to be small and lightweight in order to be mounted on a carriage, so there is a limit to the amount of ink it can hold. Therefore, the user can be notified or recognized when the remaining amount of ink reaches a certain level. Specifically, the following measures are being taken.

(a) Determination is made by detecting a change in the weight of the ink cartridge.

(b) An electrode is provided at the bottom of the ink cartridge, and the determination is made based on the change in electrical resistance.

(c) A photo sensor is installed in the ink cartridge, and determination is made by obtaining a light reception signal when the amount of ink drops to a certain level.

In addition, as a simple method, the ink cartridge has been made of a transparent material and the user has visually inspected the ink cartridge, or the ink has run out and poor printing has occurred.

FIG. 7 is a sectional view showing an example of a conventional ink cartridge.

31 is a cartridge case, 32 is a head, 33 is an ink supply tube connecting the ink cartridge and head 32, 34 is an ink bag filled with ink 37, 35
36 is a switch provided at the top of the cartridge case 31, and 36 is a lever whose one end can come into contact with the operating piece of the switch 35 and whose other end can come into contact with the top of the ink bag 34, making a see-saw movement.

In the above configuration, when there is a sufficient amount of ink 37 in the ink bag 34, the ink bag 34 is swollen and the other end of the lever 36 is pushed up, and one end of the lever 36 is in a lowered state, so that the switch 35 is turned off. has been done.

When the ink bag 34 deflates due to ink consumption, the lever 3
6 rotates counterclockwise while maintaining a balance between the biasing force of the spring and the expansion force of the ink bag 34, and finally pushes up the operating piece of the switch 35, turning the switch 35 on. This lets you know that the amount of ink has decreased to the specified amount, and that it is time to replace the ink cartridge.

[Problem to be solved by the invention]

However, in conventional ink cartridges like this, when the remaining amount of ink is detected electrically or mechanically,
The structure has become complicated and the number of parts has increased, leading to decreased reliability and increased costs.

In a configuration where the ink cartridge is transparent, in the case of a carriage-mounted type, it can only be checked while the carriage is stopped, which causes the remaining ink level to drop more than necessary, and there are inconveniences such as structural restrictions to enable visibility. .

Furthermore, in a fixed type cartridge that cannot be attached or detached, although there is a sufficient amount of ink remaining, there is a restriction on the installation space, and there are also restrictions on the installation position in order to facilitate visual recognition.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink cartridge that can solve the problems of the prior art and allows the remaining amount of ink to be determined with a simple configuration.

[Means to solve the problem]

The present invention achieves the above object by encapsulating at least one type of ink having a different concentration in a layered manner in recording ink, or by encapsulating the recording ink in a separated state until a predetermined remaining amount is reached. It is something to be achieved.

It is desirable that the inks having different concentrations have different specific gravities in order to avoid mixing with the recording ink.

In addition, in order to prevent inks with different concentrations from mixing with recording ink, inks with different concentrations are sealed in small-volume thin-film ink bags, or a part of the ink bag for recording ink is sealed. Alternatively, when the remaining amount of the recording ink reaches a predetermined value, the thin film ink bag may be ruptured or the sealed portion may be communicated with the recording ink storage portion.

[Effect]

Warning inks with different densities are supplied to the nozzles of the head following the recording ink when the recording ink is sufficiently consumed, and the print color on the recording paper changes midway through recording. You can tell when the amount of ink remaining is low.

The ink having different density and specific gravity is not mixed with the recording ink, and is sent to the nozzle of the head when the recording ink is finished. Since the two types of ink do not mix, there is no need to provide a means for separating the two.

By housing inks of different concentrations in a thin film ink bag or sealing a portion of the recording ink bag, separation from the recording ink is achieved and mixing of the two types of ink is prevented. Further, by bursting the thin film ink bag or communicating the two ink storage parts, ink of a different density is supplied to the nozzle of the head following the recording ink, and printing is performed subsequent to the printing with the recording ink.

〔Example〕

The present invention will be specifically described below with reference to FIGS. 1 to 6.

FIG. 1 is a sectional view showing an embodiment of an ink cartridge according to the present invention, and FIG. 2 is a perspective view of the main parts of an ink jet recording apparatus suitable for use with the ink cartridge of the present invention.

In FIG. 1, 1 is a cartridge, and recording ink 4 is sealed inside. A warning ink 5 having a density different from that of the ink 4 and having a light specific gravity is sealed on the surface of the ink 4. A joint rubber 6 is fitted into the bottom of the ink cartridge 1 and holds one end of a pipe 3 connecting the head 2 and the ink cartridge 1 under pressure. Further, on the top surface of the ink cartridge l, a hole 8 is provided for communicating the air layer above the ink 4 with the atmosphere.
is provided.

Next, in FIG. 2, reference numeral 10 denotes a carriage that carries the ink cartridge L and the recording/rad 2 and moves back and forth in the main scanning direction, 11 a guide that supports the carriage 10 in a movable manner, and 12 other than the guide 11. A chassis for fixing a recording paper transport mechanism, etc.; 13, a paper guide that supports the recording paper 15 in front of the head; 14, a motor serving as a drive source for transporting the recording paper 15 according to the recording situation; 16;
is a recovery system to prevent head nozzle clogging, 1
7 is a motor for moving the recovery system 16 back and forth with respect to the head 2.

In FIG. 2, when recording, the paper guide 13
Center the recording paper 15 along the lines and enter the recording mode by operating the start button or the like. By this operation, the carriage 10 moves to the printing start position, the energy generator provided in the nozzle of the head 2 is driven according to the recording data, and ink droplets are ejected from the nozzle toward the recording paper 15.

The flying ink droplets adhere to and are absorbed by the surface of the recording paper 15 to become recording dots. Each time the printing of a dot row is completed, the carriage 2 moves by a predetermined pitch, and the next digit is printed. - When printing for a line is completed or a carriage return (CR) is input, the carriage 10
is returned to the printing start position.

Note that the carriage 10 is moved to the home position periodically or as needed, and a nozzle recovery operation is performed. The recovery operation is performed by rotating the recovery system 16 by rotating the motor 17.
This is done by moving the cap 18 forward toward the head side and bringing the cap 18 into close contact with the head face.

The ink supply to the head 2 is from the ink cartridge 1.
This is done via pipe 3. The ink 4 is consumed as the recording operation progresses, and the ink 5 decreases following the decrease in the ink 4. When the ink 4 falls below the upper end of the pipe in the cartridge, the ink 5 is sent to the head 2 through the pipe 3, becomes ink droplets, flies to the recording paper 15, and adheres to the recording paper 15.

Since ink 5 has a density different from that of ink 4, it can be easily determined from the difference in recording density that the amount of ink remaining is small.

FIG. 3 is a sectional view showing another embodiment of the present invention.

This embodiment differs from the previous embodiments in that recording ink 4 is sealed in an ink bag 21, and this ink bag 21 is housed in a case 20.
The ink bag 22 made of a thin film encapsulating A is placed inside the ink bag 21.

Next, the operation of the configuration shown in FIG. 3 will be explained with reference to FIG. 4. When a sufficient amount of ink 4 remains in the ink bag 21, the ink bag 22 floats inside the ink bag 21 and is located on the ceiling, as shown in FIG. Further, the ink bag 21 is expanded so as to come into close contact with the inner surface of the case 20.

As the ink 4 continues to be consumed, since the ink bag 21 is flexible, its shape collapses depending on the amount of ink 4 remaining. At this time, the ink bag 22 is positioned at the top so as to be surrounded by the ink bag 21.

When the ink 4 is further consumed from this state, the ink bag 21 is deformed as shown in FIG. 4, the negative pressure inside the bag increases, and the ink bag 22 ruptures due to this negative pressure. Ink bag 22
When the ink 5A ruptures, the ink 5A flows through the pipe 3 to the head 2.
The ink is sent to ink 4 and used for recording instead of ink 4. By changing the ink density, the user can know that the amount of ink remaining is small.

Although the ink bag 22 is ruptured by the negative pressure generated within the ink bag 21, the needle-like tip 3A formed at the tip of the pipe 3 may be pierced into the ink bag 22.

FIG. 5 is a sectional view showing a third embodiment of the present invention.

In this embodiment, an ink bag 23 containing ink 4 is provided so that one of the side surfaces of the case 20 serves as a bottom surface, and the upper part of the ink bag 23 is bent to form a small volume ink bag 23A. The feature is that the ink 5A is sealed inside the ink bag 23A. The constriction between the ink bag 23 and the ink bag 23A becomes a valve structure 23B.

Next, the operation of the embodiment shown in FIG. 5 will be explained with reference to FIG. 6.

When the ink bag 23 is sufficiently filled with ink 4, the ink bag 23 is inflated as shown in FIG. 5, and the valve structure 23B is in contact with the wall surface of the case 20. Therefore, the ink 5A is stored sealed in the ink bag 23A at the time of shipment. Contact between the valve structure 23B and the wall surface is maintained until the ink 4 in the ink bag 23 is considerably consumed.

When a small amount of ink 4 remains in the ink bag 23, a large negative pressure is generated in the ink bag 23 and the ink bag 23 deforms in a undulating manner, causing the valve structure 23B to separate from the inner wall surface of the case and enter the valve open state. As a result, the ink 5A in the ink bag 23A mixes with the ink 4 in the ink bag 23, and the density of the print recorded on the recording paper 15 changes. From this change in density, the user can know that the amount of ink remaining in the ink cartridge is low.

In addition, in the above embodiment, only one type of warning ink 5A is used, but multiple types of ink having different concentrations and specific gravity may be sealed to issue a warning in stages. .

〔Effect of the invention〕

As is clear from the above (according to the present invention, at least one type of ink having a different concentration is sealed in a layered manner in recording ink, or the recording ink is separated until a predetermined remaining amount is reached). Since the ink is sealed in this state, the remaining amount of ink can be checked with a simple configuration.

Furthermore, by making the density and specific gravity different, a means for separating the ink from the recording ink becomes unnecessary, which further simplifies the configuration.

In addition, in order to prevent inks of different concentrations from mixing with recording ink, inks of different concentrations are sealed in a small volume thin film ink bag, or a part of the ink bag of recording ink is sealed. When the remaining amount of recording ink reaches a predetermined value, the thin film ink bag may be burst or the sealed portion may be communicated with the recording ink storage portion.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of an ink cartridge according to the present invention, FIG. 2 is a perspective view showing the main parts of an inkjet recording apparatus suitable for use with the ink cartridge of the present invention, and FIG. 3 is a cross-sectional view showing an embodiment of the ink cartridge according to the present invention. 4 is an explanatory diagram of the operation of the embodiment of FIG. 3, FIG. 5 is a sectional view of the third embodiment of the present invention, and FIG. 6 is an implementation of the embodiment of FIG. FIG. 7 is a sectional view showing an example of a conventional ink cartridge. 1------1~.-ink cartridge, 2-1--head, 3--------pipe,
4---------Recording ink, 5.5A Warning ink, 20-----1----Case, 21
．． 22.23.23B----1---Ink bag. Agent Patent Attorney Yasutake Ooto

Claims (4)

[Claims] (1) In an ink cartridge that supplies recording ink to an inkjet recording head, at least one type of ink with a different concentration is sealed in a layer with respect to the recording ink, or the recording ink is kept at a predetermined remaining amount. An ink cartridge characterized by being sealed in a separated state until the (2) The ink cartridge according to claim 1, wherein the inks having different concentrations further have different specific gravities. (3) The ink having different concentrations is sealed in a thin film ink bag having a small volume, and the thin film ink bag is ruptured when the recording ink reaches a predetermined remaining amount. ink cartridge. (4) The ink having different concentrations is sealed in a part of the ink bag containing the recording ink, and when the recording ink reaches a predetermined remaining amount, the ink having the different concentration is added to the recording ink bag. The ink cartridge according to claim 1, wherein the ink cartridge is supplied to the ink storage section.