JPH08290581A - Ink supplying device and recorder using the same - Google Patents

Abstract

PURPOSE: To detect the residue of ink even when an ink holding material is disposed in an ink cartridge. CONSTITUTION: An ink cartridge 1 is partitioned by a partition plate 13 to a space layer 11 and an ink holding material layer 12 for filling ink holding material 14, an electrode 2 is provided at the layer 11, connected with a voltage generator 3 and a current detector 4, and controlled by a controller 6. Many fine pores are provided at the plate 13. The layer 12 is connected to an ink jet recording head 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for supplying ink to an ink jet type recording head including a valve jet type used in facsimiles, printers and the like, and a recording apparatus using this apparatus.

[0002]

2. Description of the Related Art FIG. 3 shows an example of a conventional ink jet recording apparatus for detecting the remaining amount of ink. The ink cartridge 101 is filled with ink,
It is necessary to measure the remaining amount of ink as it decreases with use. The two electrodes 102 are arranged with a predetermined interval, and the current value or resistance value when ink is present or not present between them is measured. The voltage generator 103 applies a predetermined voltage between the electrodes 102, and the current detector 104 detects the value of the current flowing between the electrodes 102. An ink supply port 107 is provided at the bottom of the ink cartridge 101, and the ink jet recording head 105 and the ink supply port 10 are provided.
7 is connected by a tube 106, and ink is supplied to the inkjet recording head 105.

In FIG. 3, if the ink is filled up to the position shown by the arrow a, the space between the electrodes 102 is filled with ink, and if the ink is reduced to the position shown by the arrow b, a gap is formed between the electrodes. Generally, the resistance value of water-based ink is several KΩ
Therefore, whether the ink is filled between the electrodes can be detected by the resistance value between the electrodes 102. That is, the remaining amount of ink can be detected by applying a predetermined voltage between the electrodes 102 by the voltage generator 103 and detecting the value of the current flowing through the electrodes 102 by the current detector 104.

[0004]

However, the above-mentioned device has the following problems. In the case of an ink cartridge of a type in which ink is not directly filled in the ink cartridge 101, but an ink holding material such as sponge is provided in the ink cartridge 101 and ink is filled in the ink holding material, the contact between the ink holding material and the electrode 102 does not occur. If there is a gap between them completely, even if a sufficient amount of ink is present in the ink holding material, the electrodes 102 are insulated from each other and become in the same state as when there is no ink, which causes a problem that the remaining ink amount cannot be correctly detected. .

Further, as another problem, when the remaining amount of ink becomes small, it becomes difficult to distinguish it from the absence of ink below a certain amount, and it is detected that there is actually a small amount of ink remaining. Also, for example, the ink cartridge 10
Even if it is possible to accurately detect the absence of ink in the ink cartridge 1, it is not possible to detect the amount of ink remaining in the tube 106 and the inkjet recording head 105 after the ink cartridge 101.

As another method of detecting the remaining amount of ink, there is a method of integrating the number of times ink is ejected from the ink jet recording head 105. Since this method does not use electrodes, the above-mentioned problems do not occur even in the case of a cartridge using an ink holding material. However, the amount of ink ejected varies depending on the ambient temperature, the image frequency, and the like, and also varies among the inkjet recording heads 105. Therefore, when detecting the remaining ink amount by integrating the number of ink ejections, it is necessary to cover these error factors and calculate when the ink ejection amount is the maximum, and to detect that ink is running out even if ink actually remains. And waste of ink occurs.

The present invention has been made in view of the above problems, and it is an object of the present invention to detect the remaining amount of ink even when there is an ink holding material such as sponge in the ink cartridge. Another object is to improve the detection accuracy of the remaining ink amount by detecting the ink remaining in the ink jet recording head and the communication path from the ink cartridge to the ink jet recording head.

[0008]

In order to achieve the above object, in the invention of claim 1, an ink tank for storing ink and a partition plate for dividing the ink tank into a first space portion and a second space portion are provided. And an ink holding material filled in the first space, and a detection means for detecting the remaining amount of ink in the second space, and the partition plate allows the ink to pass therethrough. It has a hole having a size that prevents the holding material from passing therethrough, and the first space portion is adapted to supply ink to the inkjet recording head.

In the invention of claim 2, the hole of the partition plate is formed in the vicinity of the lower portion of the partition plate.

According to the third aspect of the invention, the holes of the partition plate are randomly formed over the entire partition plate.

According to the fourth aspect of the present invention, the detection means detects the remaining amount of ink by detecting the impedance of the space layer in the second space.

According to the invention of claim 5, an ink tank for storing ink, a partition plate for dividing the ink tank into a first space portion and a second space portion, and the first space portion are filled. The partition plate includes an ink holding member, a detection unit that detects the remaining amount of ink in the second space, and an ink jet recording head that is supplied with ink from the first space to perform recording on a recording medium. Has a hole having a size that allows the passage of ink but prevents the passage of the ink holding material.

According to the invention of claim 6, an ink tank for storing ink, a partition plate for dividing the ink tank into a first space portion and a second space portion, and the first space portion are filled. An ink holding material; a first detecting means for detecting the remaining amount of ink in the second space; an ink jet recording head for supplying ink from the first space to perform recording on a recording medium; Second detection for counting the number of ejections of the ink jet recording head after the amount of ink in the space 2 is reduced and the first detection means cannot detect the second ink, and the remaining amount of ink is detected from this count value. And means,
The partition plate has a hole portion having a size that allows the ink to pass therethrough but prevents the ink holding material from passing therethrough.

[0014]

According to the first aspect of the present invention, the ink tank is divided into the first space portion and the second space portion by the partition plate, and the first space portion is filled with the ink holding material for holding ink. A detection means for detecting the remaining amount of ink is provided in the second space portion. The partition plate allows the ink to pass through but prevents the ink holding material from passing therethrough. Therefore, if there is ink in the first space, the ink also exists in the second space, and the presence of this ink is detected. By detecting by the means, it is possible to detect the remaining amount of ink without the ink holding material hindering the detection of ink.

According to the invention of claim 2, since the hole of the partition plate is formed in the vicinity of the lower part of the partition plate, the ink accumulated in the first space is surely accumulated in the second space, and the ink remains. The amount can be detected accurately.

According to the third aspect of the invention, since the holes of the partition plate are randomly formed over the entire partition plate, the ink levels in the first space and the second space are the same on average, The remaining amount of ink in the first space can be accurately detected.

According to the invention of claim 4, the detecting means is the second one.
The impedance of the space layer of the space is detected. Since the impedance changes depending on the amount of ink in the space layer, it is possible to detect the remaining amount of ink.

According to a fifth aspect of the invention, the recording apparatus is configured by providing the ink jet recording head in the first aspect of the invention, and the recording apparatus can accurately detect the remaining amount of ink even if the ink holding material is provided. Is obtained.

According to the invention of claim 6, the invention of claim 5 is provided with the second detecting means for counting the number of ejections of the ink jet recording head to detect the remaining amount of ink. The remaining amount of ink remaining in the ink jet recording head and the inside of the tube from the first space to reach the remaining ink amount can also be detected. . The ink remaining in the ink jet recording head and the tube and the number of ejections of the ink jet recording head shall be investigated in advance.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view and a block diagram showing the configuration of the embodiment. The ink cartridge 1 is made of an insulating material such as plastic and is composed of an ink holding material layer 12 filled with an ink holding material 14 such as sponge and a space layer 11 not filled with the ink holding material 12, and an ink holding material layer 12 The space layer 11 is divided by a partition plate 13. Partition plate 13
Has a large number of minute holes through which the ink can pass but the ink holding material 14 cannot pass.
The ink freely flows between 2 and the space layer 11. Also,
Since the pressures applied to the upper portions of the ink holding material layer 12 and the space layer 11 are the same, the ink levels of the space layer 11 and the ink holding material layer 12 are the same height.

The electrode 2 is provided inside the ink cartridge 1, and a voltage is applied between the electrodes 2 by the voltage generator 3 via the space layer 11. The current detector 4 is connected in series with the voltage generator 3 and the electrode 2, and detects the current flowing between the electrodes 2. The counter 5 counts a signal c from a recording unit (not shown). The signal c is a pulse signal generated according to the number of inks effectively consumed in the inkjet recording head 7, and is generally generated during black signal recording, and indicates the number of ejections of the inkjet recording head 7. The control unit 6 controls the voltage generation unit 3 and the counter 5, and reads the output signal of the current detection unit 4 and the count value of the counter 5 to detect the remaining ink amount. Since the remaining ink amount is detected by the number of times the ink jet recording head 7 is ejected, the detection error is small because the amount of ink in the tube and the small amount of ink in the ink jet recording head is detected.

The controller 6 applies a voltage between the electrodes 2 to the voltage generator 3 by the signal a, and initializes the count value of the counter 5 by the signal b. The counter 5 updates the count value with the signal c. The count value is output to the control unit 6 as a signal d.

The ink jet recording head 7 is connected to an ink supply port 9 provided on the lower surface of the ink cartridge 1 by a tube 8, and ink is supplied from the ink supply port 9 through the tube 8 to the ink chamber of the ink jet recording head 7. To be done.

Next, the operation of the controller 6 will be described. FIG. 2 is an operation flow chart of the control unit. The ink remaining amount detecting operation will be described below with reference to FIGS. 1 and 2. The controller 6 carries out the operation shown in FIG. 2 at an appropriate timing, for example, at the start of the recording operation or at a fixed time interval. The control unit 6 turns on the signal a, causes the voltage generation unit 3 to generate a predetermined voltage, and
A voltage is applied between them (S1). At this time, the impedance between the electrodes 2 of the space layer 11 changes greatly depending on the presence or absence of ink. That is, if one looks at the resistance value, the ink is
Is several kilo-ohms if it is above the level, but if there is no ink between the electrodes 2, it becomes on the order of mega-ohms, and the difference can be easily detected. Also, if you look at capacitance,
The capacitance between the electrodes 2 is proportional to the permittivity of the space layer 11, but since the permittivity of ink is about two orders of magnitude higher than that of air, this can also be easily detected. When the ink level is within the height of the electrode 2, a resistance value corresponding to the level is detected, so that the approximate level can be estimated.

The change in impedance can be detected as a change in the value of the current flowing between the electrodes 2. The control unit 6 reads the output of the current detection unit 4 (S2) and estimates the remaining amount of ink by detecting the impedance between the electrodes 2. When it is determined that the remaining amount of ink is less than the predetermined amount, that is, the ink is almost completely out of the ink cartridge 1 (S3), the signal b is turned on and the counter 5 is initialized (S4). After that, the counter 5 updates the count value every time the signal c is turned on.
Thus, the consumption amount of the ink remaining in the tube 8 and the inkjet recording head 7 is measured. The control unit 6 checks the count value of the counter 5 sent by the signal d (S5), and reaches the predetermined value, that is, the value estimated that the ink remaining in the tube 8 or the inkjet recording head 7 is almost exhausted. When it does, it informs the outside that there is no ink (S6). Thereby, the remaining amount of ink can be managed accurately. The relationship between the number of ejections of the inkjet recording head 7 and the amount of ink remaining in the tube 8 and the inkjet recording head 7 is to be investigated in advance.

In the above-mentioned embodiment, the electrode 2 is provided inside the ink cartridge 1 so as to be in contact with the ink, but it may be provided outside. This can prevent the electrode 2 from being corroded by the ink. Further, the partition plate 13 itself may be provided with a gap between the bottom surface of the ink cartridge 1 and the lower end of the partition plate 13 without providing the ink circulation hole.
Although the partition plate 13 is a flat plate in the embodiment, the electrode 2 is provided as the air layer 11 in the shape of a cylinder, the ink holding material layer 12 is provided on the outer side, and the cylindrical partition plate 13 is provided with a number of minute holes. Good. In addition, the ink holding material layer 12 is provided inside the cylinder, the air layer 11 is provided outside, and the electrode 2 is provided.
It is also possible to provide a large number of minute openings.

[0028]

As is apparent from the above description, according to the present invention, the ink tank is divided into the first space portion filled with the ink holding material by the partition plate and the second space containing only the ink, and the second space is provided. By detecting the ink remaining amount in the space, the ink remaining amount can be detected even in the ink cartridge using the ink holding material. Further, by counting the number of ejections of the ink jet recording head, it is possible to detect the ink remaining amount in the ink jet recording head or the tube connecting the ink jet recording head and the ink tank.

[Brief description of drawings]

FIG. 1 is a perspective view and a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is an operation flow chart of the embodiment.

FIG. 3 is a block diagram of a conventional ink remaining amount detection circuit.

[Explanation of symbols]

 1 Ink Cartridge 2 Electrode 3 Voltage Generation Section 4 Current Detection Section 5 Counter 6 Control Section 7 Inkjet Recording Head 11 Space Layer 12 Ink Holding Material Layer 13 Partition Plate 14 Ink Holding Material

Claims (7)

[Claims] 1. An ink tank for storing ink, a partition plate for dividing the ink tank into a first space portion and a second space portion, and an ink holding material filled in the first space portion, A detecting means for detecting the remaining amount of ink in the second space portion, wherein the partition plate has a hole portion having a size that allows passage of ink but prevents passage of the ink holding material, The first space portion is adapted to supply ink to an ink jet recording head. 2. The ink supply device according to claim 1, wherein the hole of the partition plate is formed in the vicinity of the lower portion of the partition plate. 3. The ink supply device according to claim 1, wherein the holes of the partition plate are randomly formed over the entire partition plate. 4. The ink supply apparatus according to claim 1, wherein the detection unit detects the remaining amount of ink by detecting the impedance of the space layer in the second space. 5. An ink tank for storing ink, a partition plate for dividing the ink tank into a first space portion and a second space portion, and an ink holding material filled in the first space portion, The partition plate includes a detection unit that detects the remaining amount of ink in the second space and an inkjet recording head that is supplied with ink from the first space to record on a recording medium. A recording apparatus having a hole portion that is capable of preventing ink from passing therethrough. 6. An ink tank for storing ink, a partition plate for dividing the ink tank into a first space portion and a second space portion, and an ink holding material filled in the first space portion, First detecting means for detecting the remaining amount of ink in the second space, an ink jet recording head for supplying ink from the first space to perform recording on a recording medium, and ink for the second space And a second detecting means for counting the number of jets of the ink jet recording head after the first detecting means becomes undetectable and detecting the remaining amount of ink from the counted value, The recording apparatus, wherein the partition plate has a hole portion having a size that allows the ink to pass therethrough but prevents the ink holding material from passing therethrough. 7. The recording apparatus according to claim 5, wherein the detecting means is provided outside the ink tank.